Toxic dose of paracetamol. Paracetamol lethal dose how many tablets

Paracetamol is one of the most popular drugs that is in almost any first aid kit. From fever and pain, and almost from a bad mood, people are used to taking paracetamol, and just as easily and without thinking about the possible consequences, they give it to children. Since this substance has been proven to be effective for decades and is an active ingredient in more than 100 drugs, at first glance, there is nothing wrong with this. It is not for nothing that paracetamol is one of the most important medicines recommended by WHO. However, the specificity of paracetamol is such that it requires precise adherence to the dosage and regimen, and also does not allow self-medication.

Paracetamol: benefits and harms to the body

Paracetamol-based preparations perfectly relieve even severe pain, as they depress pain centers, they warn inflammatory processes and regulate the work of the thermoregulation center of the brain, and act quickly and retain their effect for up to 6 hours. If paracetamol is used in the doses recommended by the instructions, it is characterized by low toxicity and, at the same time, high efficiency, so the worldwide popularity of drugs based on it is completely understandable and deserved. That is why paracetamol is among those allowed for use even by small children up to a year old: children's Panadol is based on paracetamol.

But if all this is so, is it possible to poison yourself with paracetamol?

Paracetamol forms compounds that are hazardous to health during metabolism, which normally bind in the liver and are safely excreted from the body if the dose was therapeutic. If there is an overdose, the body simply may not have enough of the binding component - glutathione, and then the decay products of paracetamol are bound by proteins of liver cells, which die as a result - this is what paracetamol is dangerous for. However, the harmful effects are not limited to this: virtually all key organs are affected: the heart, kidneys, pancreas and central nervous system.

Paracetamol poisoning is possible in the case of:

erroneously high doses (this happens with old people who take drugs uncontrollably, and with babies who suddenly get to the first-aid kit and are able to immediately drink a bottle of children's remedy for fever and pain, because it has such a sweet, pleasant taste!)
taking several drugs based on paracetamol at the same time: even if the dosage of each drug was not exceeded, in total they give an overdose;
taking several drugs that affect the liver at once: drugs with paracetamol, antihistamines, barbiturates (hypnotics and sedatives);
taking drugs based on paracetamol along with alcohol: for the period of treatment, any alcohol is strictly prohibited, as it additionally jeopardizes the work of the liver;
the use of medicines based on paracetamol for liver diseases (this is a contraindication for taking);
prolonged and uncontrolled use of the drug in large doses;
in cases of individual intolerance (allergic reaction or hypersensitivity to the drug)
with intentional poisoning (suicide).

What are the symptoms of paracetamol overdose?

You need to know the symptoms of intoxication in order to prevent trouble in time: focusing on outward signs, you can save health and even life, for example, little child or an elderly person.

Paracetamol-based preparations act somewhat differently on adults and children. Also they have various features impact on different stages intoxication. If we are dealing with acute poisoning, then the picture will look like this:

Stage one: the first day there are signs of general intoxication: bad feeling, pallor and sweating, headache, nausea, sometimes vomiting, refusal to eat due to lack of appetite. However, if tests are taken at this time, they will be within the normal range.
Stage two: after 24 hours, symptoms of liver damage begin to appear: heaviness and pain under the ribs on the right, and blood tests show elevated level liver enzymes. But the previous symptoms gradually disappear, because of which it may seem that the malaise recedes.
Stage 3: On days 3-5 without assistance, the liver gradually dies.
- The whole body swells and multiple bleedings are observed (from the gums, stomach, nasal, etc.)
- There are disturbances in the functioning of the brain () - alternation of excitement and drowsiness, convulsions can be observed, speech is disturbed, thinking becomes slow, delirium and hallucinations appear, consciousness is confused - up to a coma.
- Tests show a very high level of liver enzymes and bilirubin, and the acidity of the blood increases due to the formation of lactic acid - these are symptoms of acidosis.
- The skin and mucous membranes become yellowish, the pain in the hypochondrium on the right is very strong, there is absolutely no appetite and vomiting follows vomiting.
- Urine becomes less and less until urination disappears altogether.
- Cardiac activity is also disturbed, tachycardia is observed.
- Body temperature drops.
- There is a decrease in the size of the liver.
- Another sign is an unpleasant "liver" smell from the mouth.
Stage 4. After 5 days, if help did not come or the treatment was ineffective, the person dies due to the failure of all organs and systems, massive bleeding, sepsis (blood poisoning) and cerebral edema. If a person received adequate treatment or at least took an antidote on time, at this stage the body's work is restored and functions are normalized - lasting up to 14 days.

With chronic overdose of paracetamol, symptoms such as:

loss of appetite and frequent nausea and vomiting;
inexplicable lethargy, apathy;
yellowish tint or pallor of the skin and mucous membranes;
bleeding gums or from the nose, the appearance of bruises (hematomas) on the body;
discomfort or pain on the right under the ribs.

An overdose of antipyretics in a child

If an overdose of paracetamol occurred in a baby, especially younger than 6 years old, then, surprisingly, the process is not as difficult as in adults, and the consequences are not so formidable: at least, liver damage is not so pronounced and critical. This is explained by the peculiarities of metabolic processes in children: their intensity and speed are much higher, so the body is much more likely to cope with intoxication on its own.

However, this does not mean that taking paracetamol-containing drugs for a child is safe and that it can be self-prescribed and dosing carelessly. A lighter course and consequences does not mean their absence, and in severe cases, a tragic outcome is also possible.

In addition, if we talk about newborn babies (less than 1 month old), then an overdose of paracetamol is extremely dangerous for them. It can instantly stop the liver and cause the death of the child. That is why young children are prescribed medicines for fever and pain from those that do not contain paracetamol.

Consequences of intoxication with paracetamol

Paracetamol poisoning can result in:

acute liver and kidney failure, acute pancreatitis, as well as failure of all organs and systems of the body;
brain damage (encephalopathy) of toxic origin;
pulmonary edema of toxic origin;
heart complications - myocarditis;
coma and death.

Since the main target of paracetamol is the liver, in case of an unfavorable development of events, a liver transplant may even be required. If the treatment was started on time and carried out correctly, the prognosis of the condition is considered favorable.

Antidote for paracetamol overdose

Is it possible to avoid such severe consequences?

Of course, yes - if you take an antidote in the first 8 hours after poisoning, which is acetylcysteine (it is he who is the active ingredient in the ACC drug, a popular cough medicine sold in any pharmacy). Its action is aimed at binding and neutralizing, and then removing from the body the toxic decomposition products of paracetamol. AT medical institution the antidote, of course, is administered not only in the form of tablets, but also by intravenous injections.

First aid for paracetamol poisoning

If the situation is such that it is you who urgently needs to be treated for an overdose of paracetamol, you need to act quickly and according to the rules:

call immediately ambulance.
Rinse the stomach with a drink a large number of salted water (at least a couple of glasses), and if necessary, by pressing on the root of the tongue to initiate vomiting.
Take (polyphepan, polysorb, etc.) to bind and remove toxins. It is important to know that activated carbon blocks the action of the acetylcysteine antidote, so they cannot be used at the same time: if an antidote is introduced, coal is not used as a sorbent.
Take a laxative to cleanse the bowels.

Preventive measures

It is important to follow these simple rules. and thereby protect yourself from severe poisoning:

Keep paracetamol (as well as the rest of the first aid kit) in a place completely out of the reach of children.
Take drugs with paracetamol only according to the scheme indicated by the doctor or in the instructions (with the obligatory maintenance of a four-hour interval and no longer than 5 days).
Do not self-medicate and do not take (and also do not give children) paracetamol for any reason, this can lead not only to intoxication, but also to others. negative consequences: for example. to an increased risk of developing asthma.
Do not use expired drugs: their effectiveness is reduced and there is a desire to achieve the desired result by increasing the dose, which is fraught with an overdose with all its unpleasant consequences.
Strictly adhere to contraindications, do not take drugs with paracetamol or reduce their dose to a minimum (as the doctor decides):
- in diseases of the liver, kidneys and gastrointestinal tract
- with bronchial asthma
- pregnant in the last trimester
- people with individual intolerance
Do not combine the use of drugs with:
- drinking alcohol (here the prohibition is categorical, even if it is “just” beer);
- taking medications that enhance the effect of paracetamol;
- taking medications that also contain paracetamol.

Be careful with the use of even familiar and seemingly harmless drugs, such as paracetamol, and this will save your health.

Paracetamol consists of the main active substance- acetaminophen. It is a component of more than 200 medicines, including in many children's medicines - syrups, capsules, tablets, suppositories. These are anti-influenza and painkillers.

Due to its prevalence, overdoses of this drug are common. What doses are acceptable, when poisoning can occur, the symptoms of such intoxication, and how to cleanse the body of this medicine? Let's discuss this.

In what cases can you get poisoned

Paracetamol poisoning can occur in several cases:

when taking large doses once;
with prolonged use of the drug;
with increased sensitivity to it.

Paracetamol's antidote, N-acetylcysteine, is known to medical professionals. It must be taken within the first 8 hours after taking an overdose of paracetamol.

What doses of paracetamol are acceptable

Before starting treatment, be sure to study the drug, check the dosage! Paracetamol is taken orally, washed down with plenty of liquid.

A single dose for adults is 500 mg for a person weighing up to 40 kg, and 1 gram for a person weighing more than 40 kg. The number of doses per day is a maximum of 4. The maximum daily dose is 4 grams for an adult, 90 mg per kg of weight for children. The duration of the course of treatment is 5-7 days.

The lethal dose is calculated and is more than 150 mg per kilogram of body weight for an adult.

Is it possible to get poisoned with paracetamol, observing the maximum daily dose? Yes, its toxic effect, up to poisoning, can also occur when taking an acceptable dosage of the drug. This is observed in alcoholism, hepatitis, starvation, hereditary diseases liver, co-administration of such drugs as: Rifampicin, Isoniazid, anticonvulsants.

What is harmful paracetamol

Once in the stomach, paracetamol is rapidly absorbed and enters the bloodstream. The main breakdown of the drug into metabolites occurs in the liver cells, which are excreted in the urine. The disintegration period is 1.5–2 hours, but due to the long-acting properties of this drug, absorption and breakdown continues in the small intestine.

The main metabolite is N-acetyl-b-benzoquinoneimine, which is formed in the liver and has a toxic effect. It is neutralized by glutamine in the liver. With the depletion of reserves and deficiency of glutamine, the accumulation of a metabolite occurs, which has a toxic effect on the liver, kidneys and pancreas. Depletion of glutamine reserves is observed when taking more than 10 grams of paracetamol.

Poisoning is possible at any age. But in children, paracetamol poisoning rarely leads to liver failure, as they are resistant to toxic effects.

Symptoms of paracetamol poisoning

Symptoms of paracetamol poisoning after 10-24 hours:

nausea and vomiting;
severe pain in the right hypochondrium;
aversion to food;
malaise and general weakness.

Symptoms of paracetamol poisoning after 36 hours:

With the appearance of such symptoms of paracetamol poisoning, emergency hospitalization of the victim is necessary.

Clinical picture of paracetamol poisoning

Allocate 4 stages of the course of poisoning.

First stage. Time after taking from 1 to 24 hours.

mild degree of poisoning - no symptoms;
medium degree of poisoning - nausea, vomiting, sweating, anorexia, pallor skin, laboratory parameters are within the normal range;
severe degree of poisoning - symptoms of damage to the liver, heart and pancreas, consciousness is not disturbed, slight lethargy.

Second stage. Time after taking from 24 hours to 3-4 days. It is manifested by pain in the right hypochondrium, the size of the liver increases.

If poisoning occurred from a moderate amount of the drug, then the symptoms do not progress, and the patient recovers!

If the poisoning occurred from an overdose of the drug, then all the symptoms increase. The liver is affected, the level of AST, ALT rises to 1000 IU / l, bilirubin.

Third stage. The time after admission is 3-5 days.

With a moderate degree of poisoning - the reverse development of symptoms and recovery!

With a severe degree of poisoning, toxic liver damage increases and AST and ALT values are above 10,000 IU / l, high bilirubin levels, consciousness is disturbed, sugar levels decrease, jaundice appears, kidney failure, a sharp decrease blood pressure, body temperature.

Fourth stage. Time after taking a high dose of the drug for more than 5 days.

Irreversible liver failure with a fatal outcome.

Treatment of paracetamol poisoning

It is necessary to call an ambulance team and immediately begin to provide emergency care for paracetamol poisoning before the arrival of doctors.

Basic treatment

Gastric lavage, within one and a half hours after taking the drug.
Tablets activated carbon within 8 hours after taking the drug at a dosage of 1 gram per kilogram of body weight.
Introduction of the antidote N-acetylcysteine within 8 hours after taking the drugs.
Artificial ventilation of the lungs to accelerate the breakdown and excretion of paracetamol metabolites.
The introduction of methionine 2.5 grams orally with an interval of 4 hours three times to protect liver cells.

Symptomatic treatment

Prevention of paracetamol poisoning

By following all the rules, poisoning can be prevented:

Keep medications in places inaccessible to children.
When taking the drug, pay attention to the dosage and correctly calculate the daily dose of paracetamol.
Avoid joint reception non-steroidal anti-inflammatory drugs (Nurofen, acetylsalicylic acid, Ortofen, Ibuprofen, Metamizole sodium, Analgin), as they enhance the effect of paracetamol.
Categorical refusal of alcohol while taking paracetamol.
When taking paracetamol for more than 3 days in a row, add methionine to the treatment.

In most cases, such poisoning is due to the ability of the liver to regenerate, the presence of antidote and maintenance therapy, and with timely treatment ends with recovery.

With irreversible liver failure, an emergency liver transplantation is necessary, the prognosis is extremely unfavorable.

If you take the permissible dosage of the drug, taking into account the peculiarities of the state of health, then it will not bring any harm to health!

ACC (N-acetylcysteine) is an N-acetylated derivative of the natural amino acid L-cysteine.

Oral bioavailability ACC low, possibly due to extensive metabolism according to the first pass effect. At steady state, the volume of distribution is 0.6 l/kg. The elimination half-life for intravenous administration is close to 6 hours.

The antidote is removed from the body mainly with urine in the form of inorganic sulfate, a slightly smaller amount of taurine and the initial ACC. Pharmacokinetic studies show that the mean maximum plasma concentration of ACC is 554 mg/l after intravenous administration the first loading dose of 150 mg/kg. At this time, the development of negative reactions is most likely.

Indications. ACC (N-acetylcysteine) is indicated in the treatment of acetaminophen overdose in the following cases.
1. The plasma concentration of acetaminophen 4-12 hours after oral administration is above the "treatment line" shown in the figure below.
2. A single oral dose of acetaminophen greater than 100 mg/kg has been ingested and its plasma concentration cannot be determined.
3. There is or is very likely acute acetaminophen-induced liver failure.

Oral ACC is the only U.S.-approved antidote for general use for acetaminophen overdoses. It is categorized as an experimental drug with limited availability. ACC provides maximum protection against hepatotoxicity if administered within 8-10 hours of an acetaminophen overdose.

Then the effectiveness of its use decreases, although even when used no more than 16 hours after an overdose, not a single lethal outcome was noted. Regarding the benefits of ACC 14-36 hours after it, the data are contradictory. Studies at the hepatology department at King's College Hospital, London have shown that intravenous administration of ACC up to 72 hours after overdose reduces the risk of progression of hepatic encephalopathy to grade III/IV of this disorder and mortality from fulminant liver failure.

Late ACC therapy not associated with an increased risk of negative effects. It is likely that both the liver and the kidneys can be protected by ACC if given early. In acetaminophen-induced hepatotoxicity, administration of this antidote appears to be justified, regardless of how much time has passed since the last dose of the drug.

Start and duration of treatment paracetamol acetylcysteine (ACC) poisoning. If, based on the analysis of the nomogram, it is decided to start ACC therapy, its course should be carried out regardless of the further decrease in the level of acetaminophen, i.e. even if its plasma levels are below the "treatment line", it is not worth stopping the administration of the antidote. Patients with suspected mild overdose may wait 10 to 12 hours after oral administration of acetaminophen to determine plasma concentrations of acetaminophen without ACC administration, if required at all.

As oral loading dose 140 mg/kg give a 5% solution of ACC. The concentration of commercially available drugs is 10 and 20%, so they must be diluted. Plain water and even a carbonated flavored drink are suitable for this. Then, every 4 hours, the patient is given another 17 doses of 70 mg / kg in the form of a similar 5% solution. As a result, in 72 hours the total dose will be 1330 mg/kg.

Intravenous administration of ACC (N-acetylcysteine). In the UK and Canada, ACC is used both orally and intravenously. The advantages of intravenous ACC therapy include the possibility of treating patients with nausea and vomiting, as well as the simultaneous use of activated charcoal without reducing the plasma level of the antidote.

Although no follow-up clinical trials comparing oral versus intravenous ACC efficacy have been conducted, one retrospective controlled trial suggests that when therapy is initiated late (more than 16 hours after overdose), the first route may provide better results. Indications for intravenous use of ACC are the same as for the appointment of an oral antidote.

20 hour scheme. This approach consists of 150 mg/kg intravenously in 200 ml 5% dextrose over 15 minutes, followed by 50 mg/kg in 500 ml 5% dextrose over 4 hours, followed by another 100 mg/kg in 1 liter 5% dextrose solution for 16 hours. Thus, a total dose of 300 mg/kg is infused over 20 hours. This regimen effectively prevents liver damage, kidney failure and death if treatment is started within 8 hours of the overdose, with efficacy rapidly declining if started later. In the UK, ACC is administered intravenously in 5% glucose solution. If the patient develops stridor, flushing, or hypotension during infusion, therapy should be interrupted and symptomatic treatment of the likely allergic reaction should be carried out.

48 hour scheme. If 10-24 hours have passed since an overdose of acetaminophen, especially if a high dose of acetaminophen is taken, a 48-hour treatment regimen should be considered. US clinical trials use a total dose of 980 mg/kg ACC over 48 hours. of 12 maintenance doses of 70 mg/kg ACC intravenously. They are also administered for 1 hour each. A non-randomized trial in the USA shows that this 48-hour regimen is similar in efficacy to 20-hour intravenous and 72-hour oral administration of the antidote early.

However, if treatment is started 16-20 hours after the overdose, 48 hours of intravenous therapy appears to give better results than 20 hours.

Intravenous administration ACC within 20 hours reduces mortality when used even 24-36 hours after an overdose. Later (36 hours after it), the start of such therapy is safe.

Dose of ACC (acetylcysteine) for paracetamol poisoning. The current drug ACC (Mucomyst) is designed for inhalation use and may contain impurities. The ability to remove them with millipore filters has not been studied. The minimum effective dose has not been established, although less ACC is administered intravenously than orally. The average stationary concentration of ACC after 12 hours of a 20-hour course is 35 mg/l. The effectiveness of ACC appears to be similar for both routes of administration. Optimization of therapy for dosage and duration for high-risk patients who are treated 16 hours after an overdose requires further clinical trials.

Summarizing, we can conclude that the results of using the 20-, 48- and 72-hour (oral) courses are similar: there were no significant differences in mortality rates and consequences of poisoning when they were used.

Undesirable application effects ACC with paracetamol poisoning:

a) oral form. ACC (acetylcysteine) is not hepatotoxic. Its unpleasant odor is minimized if you drink the drug through a straw. If the patient does not tolerate oral ACC, an alternative is to administer it through a nasogastric or duodenal tube (Miller-Abbort, Cantor) with an intravenous injection of metoclopramide at a dose of 1 mg per 1 kg of body weight. Intravenous doses of ondansetron 0.15 mg/kg every 8 hours (three times in total) also increase the tolerability of oral ACC. Systemic anaphylactic reactions with this method of administration of the antidote were not observed. Sulfhemoglobinemia (cyanosis with cardiorespiratory failure, increased sulfhemoglobin levels and normal blood O2 saturation) is occasionally observed.

b) intravenous form. Approximately 3-9% of cases, approximately 15-60 minutes after the start of intravenous administration of ACC, anaphylactoid reactions (thrombocytopenia, rash, hot flashes, chest pain, tachycardia, fever, hypotension, angioedema, bronchospasm) are observed. They depend on the serum concentration of the antidote (usually begin when the latter exceeds 500 μg / l) and are probably due to a non-immunological mechanism for histamine release. In most cases, these reactions are mild and are usually treated with antihistamines, epinephrine, or a reduction in the rate of ACC infusion.

ACC in long-acting paracetamol (acetaminophen) poisoning

This oral the form appears to be similar to Tylenol Extra Strength film-coated tablets (500 mg). Assign 2 tablets (in the amount of 1300 mg) every 8 hours for adults and children over the age of 12 years. The recommended dose should not exceed 6 tablets (3900 mg) in 24 hours. The time to peak blood levels after taking 1300 mg is about 1-2 hours. Clinical and toxicological controlled studies of overdose have not been conducted. Treatment of acute cases, if no more than 8 hours have passed since ingestion, includes standard procedures for cleaning the digestive tract, determining the initial level of acetaminophen in the blood and its levels after 4 hours and later.

If they correspond areas above the lines of the nomogram, appoint ACC. Levels below 10 µg/mL do not appear to be toxic. If they are below the line of probable toxicity, but above 10 μg / ml, it is necessary to start ACC therapy and re-determine the level of acetaminophen after 4-6 hours. If the patient arrived late or took a high dose of acetaminophen, the antidote is started even before the first results of the analysis are received. If acetaminophen levels are still detectable after infusion of the standard 17 doses, prolongation of ACC therapy may be considered.

Douglas et al. consider that after a single overdose, the toxicokinetics of prolonged and regular forms of paracetamol (acetaminophen) are approximately the same, i.e. the first case does not require an alternative diagnostic approach. However, according to Graudins et al., measurement of acetaminophen levels after a massive overdose of its long-acting form may underestimate the importance of the antidote when using a nomogram based on the use of conventional paracetamol preparations.

Potentially even stronger limits the role such nomograms late drug absorption. Non-toxic levels (acetaminophen) in these graphs do not rule out subsequent hepatotoxicity. Temple and Mrazik suggest that in the event of an overdose of long-acting form of acetaminophen, plasma levels should be measured at least 4 hours after ingestion and then again 4-6 hours later. it is necessary to conduct a full course of acetylcysteine therapy. If they are below this line, toxicity is unlikely. However, if the second value is higher than the first or near the area of potential toxicity, it is desirable to additionally measure the concentrations of acetaminophen and start or continue administration of the antidote.

Paracetamol (for Latin- "Paracetamol") is an organic compound that is a derivative of an aromatic amine (aniline), in which the hydrogen atom is replaced by a carboxylic acid residue. To date, Paracetamol is the best-selling drug with analgesic and antipyretic (anti-febrile, antipyretic) action. The widespread use of paracetamol is due not only to low cost and fairly high efficiency, but also to a low degree of toxicity compared to other drugs of the anilide group. The tool is sold without a prescription, so many people buy it without consulting a doctor when pain of various localization and intensity appears. Uncontrolled use can not only cause serious side effects, but also cause an overdose, especially if a person is not limited to the minimum effective therapeutic dose and uses increased dosages of paracetamol without significant indications.

Description of the drug

Paracetamol is the main primary metabolite (decay product) of phenacetin, an unregistered and prohibited for sale in Russia in its pure form, a substance with a high degree of nephrotoxicity. In high doses, as well as with prolonged use, phenacetin can cause severe renal failure and provoke the growth of tumor formations in the urinary tract.

In terms of its structure and chemical properties paracetamol (in Europe, the drug is better known as Acetaminophen) is close to phenacetin, but has a number of advantages over its "predecessor", for example:

has low toxicity and does not have a pronounced negative effect on the functioning of the kidneys (if the instructions are followed);
rarely causes the formation of oxygen-containing metalloprotein forms of hemoglobin that are not able to bind oxygen and transport it to cells and tissues;
when used in therapeutic doses, it is well tolerated;
unlike phenacetin, paracetamol is approved for use in infants older than 1 month (in the form of suppositories and suspensions).

The drug effectively eliminates febrile syndromes by inhibiting the synthesis of prostaglandins (pain and inflammation mediators) in the central nervous system, and also reduces the degree of their effect on the thermoregulatory center in the hypothalamus. As an anesthetic, the drug is most effective for migraine, arthritis, toothache, various dorsopathies, infectious diseases accompanied by hyperthermia and fever.

Can paracetamol poison you?

Paracetamol poisoning can occur for several reasons. The first and most important of them is an overdose. The causes of overdose may be long-term use (drugs from the anilide group are not recommended for use longer than 5 days) or a violation of the dosing regimen. This situation is typical for people suffering from chronic diseases prone to relapses and exacerbations. It could be a pathology musculoskeletal system, dental diseases, disorders of the autonomic and central nervous system etc. A person experiencing severe pain tries to stop it as soon as possible, for which he takes an increased dosage of paracetamol (usually this happens several times during the day).

Another common cause of poisoning is the combination with alcoholic beverages. Despite the fact that paracetamol is less toxic compared to phenacetin and other anilides, when interacting with ethyl alcohol, which is part of almost all alcoholic beverages, it can cause severe intoxication with violation of vital functions: respiratory, cardiac contractility, CNS functioning . If a person has already taken alcohol, if possible, refuse to take aniline derivatives or reduce the dose of the drug by 1.5-2 times.

Important! Signs of an overdose in a person may appear even if he did not violate the dosing regimen recommended in the instructions. This can happen if the patient ignored the existing contraindications.

For example, in severe liver diseases, taking (especially repeated) paracetamol can cause poisoning, since 96.9% of the substance is metabolized in the liver cells, and if there are disturbances in the functioning of this organ, the metabolic process will proceed several times slower, causing acute intoxication.

Dangerous dosage

For adults, a single dose of the drug is usually 500 mg (1 tablet). At severe pain Doubling the dose is allowed, but not more than two tablets at a time. It is necessary to take the drug separately from meals. Reception after a meal reduces the absorption of the active substance by almost 43.1%, which leads to a weakening of the analgesic and antipyretic effect and forced excess of the minimum effective therapeutic dose to achieve the desired result.

Information on how many tablets you need to take in order for an overdose or poisoning to occur is indicated in the official annotation. Dangerous doses are:

3 tablets at a time - an acute overdose occurs;
4-5 tablets or more - poisoning occurs;
8 tablets per day - severe poisoning occurs;
30 tablets per day - severe liver damage occurs;
40 tablets per day (more than 15 tablets at a time) - a high probability of death due to sudden cardiac arrest or respiratory depression.

For example, tablets containing 500 mg of paracetamol (adult dosage) are indicated.

What dose can be dangerous for a child?

Paracetamol is the most prescribed drug for pain and pyrexia in children since one month old. This medicine preferred by both pediatricians and doctors of narrow specialties due to the low degree of toxicity and gentle effect on the child's gastrointestinal tract. An overdose of paracetamol in children in most cases occurs due to the fault of parents who repeatedly give the medicine at a high temperature, not maintaining the recommended interval, which is at least 3-4 hours.

Symptoms of an overdose in a child can occur even after a single dose is exceeded, which is no more than 10-15 mg / kg (up to 4 times a day). Upon detection of any of possible signs overdose, it is important to immediately call an ambulance and provide first aid at home. A dangerous daily dose of paracetamol for children is 65-70 mg/kg.

Signs and symptoms

The most common symptoms of paracetamol drug intoxication include:

pain and cramps in the abdomen (mainly spastic and cramping);
skin blanching;
changes from of cardio-vascular system(pulse disturbance, slowing down heart rate, drop in blood pressure, shortness of breath);
nausea and vomiting (vomit has a thick consistency and a rich white or milky hue);
change in taste perception, the appearance of strong bitterness and metallic taste in the mouth;
painful constipation, false imperative urge to defecate;
functional diarrhea;
tremor of the limbs;
pupil dilation;
violation of motor coordination and speech disorder (extremely rare);
yellowness of the skin and mucous membranes (with toxic liver damage).

In children early age symptoms may be manifested by frequent and profuse regurgitation of fetid masses of unnatural consistency with a pungent odor. The child may show great anxiety, refuse to breastfeed, and kick his legs. The abdomen is swollen, painful on palpation. Changes in the stool do not always occur, but more often proceed as constipation with preceding tenesmus.

Health care

The antidote of paracetamol is acetylcysteine (a substance with antioxidant, mucolytic and expectorant effects). The total dose of acetylcysteine is 300 mg per kilogram of the patient's body weight, which must be administered sequentially according to a certain scheme for 20 hours (that is, it takes a little less than a day to provide emergency care). It is necessary to dilute the drug in a 5% glucose solution.

Scheme of administration of acetylcysteine in paracetamol poisoning:

For obese persons (body weight over 110 kg), the dosage of acetylcysteine is increased by 1.5 times, while the volume of the required glucose solution remains the same.

Consequences and complications

One of the most serious consequences of paracetamol poisoning is toxic liver damage, which occurs with prolonged use of the drug at an increased dosage. The main risk factors for damage to hepatocytes while taking paracetamol are disorders eating behavior, alcoholism, extreme exhaustion of the body, a long break between meals (for example, due to severe toothache). With regular use of alcoholic beverages in large doses, a person may induce liver enzymes, which in itself is a risk factor for hepatotoxic effects, and in combination with paracetamol, alcoholic beverages can have an extremely negative effect on the liver system, as well as the functioning of the kidneys and urinary tract.

Among others possible consequences overdose can also be the following pathologies:

heavy allergic reactions(including angioedema, laryngospasm, anaphylactic shock);
hypochromasia (a group of anemias for which the color index of blood, due to a lack of normal hemoglobin, is less than 0.8 units);
methemoglobinemia (a disease in which the level of methemoglobin in the blood reaches 1% or more);
tubulointerstitial nephritis;
kidney failure.

In extremely severe cases (when using more than 40 tablets per day), death is possible, especially if a person combined the use of paracetamol with alcohol.

Paracetamol is inexpensive, effective and correct use a fairly safe drug with antipyretic and analgesic action. In case of symptoms of an overdose, it is necessary to carry out specific therapy, which consists in the infusion administration of an antidote (acetylcysteine). Further treatment includes mandatory observation in the hospital for at least 3 days, supportive and symptomatic therapy.

Paracetamol is an antipyretic. In the West, the drug is known under the name acetaminophen. available, effective medicine safe for adults and children if you follow the instructions. Medicines need to know the measure, otherwise it is easy to get poisoned even with paracetamol.

Paracetamol is an analgesic with anti-inflammatory, antipyretic properties. Non-steroid drug does not participate in biological processes, performs only the functions of anesthesia, thermoregulation. The anti-inflammatory effect is weakly expressed.

The substance captures the cyclooxygenase enzymes involved in the production of prostaglandin mediators. Getting on pain receptors, mediators increase their sensitivity. The absence of catalysts deactivates the receptors. As a result, the pain goes away. The thermoregulatory center is located in the hypothalamus of the brain. Paracetamol lowers the temperature, slowing down the work of the center.

The medicine enters the blood from the intestines, acts after 10 minutes, a maximum of an hour. The antipyretic effect persists for 6 hours. The drug processes the liver, excreted by the kidneys.

Application area

The drug is prescribed for the treatment of fever accompanying infectious, viral infections. Paracetamol eliminates various pains:

Migraine;
toothache;
neuralgia;
myalgia;
Algodysmenorrhea;
Traumatic, rheumatic pain.

The main symptom that the remedy fights is heat. The substance relieves painful menstruation - algomenorrhea, joint pain - arthralgia. Myalgia, muscle pain due to infections, injuries are treated with paracetamol.

The substance is used as the main, additional component of anti-inflammatory, anti-cold drugs. They produce candles, tablets, children's, adult syrups, sold without a prescription. The substance is part of complex powder preparations against colds - fervex, coldrex, colds.

Contraindications

Paracetamol is non-toxic at the standard dosage. Dangerous in high doses, the drug damages the liver, kidneys, heart, stomach, intestines, and central nervous system.

Chronic diseases of the liver and kidneys do not allow coping with low doses of paracetamol. It is impossible to combine the intake of alcohol with treatment with a substance due to the increased load on the liver. Other contraindications:

Allergy to analgesics;
Gilbert's syndrome;
Alcoholism;
Anemia.

Gilbert's syndrome means a constant high content of the bile pigment bilirubin in the blood. genetic disease can develop hidden, accidentally detected by the results of the analyzes. Until then, the patient may not know about it or until he overdoes it with paracetamol.

Dosage

For adults

Adults, adolescents weighing 60 kg or more should take 500 mg as a single dose, not to exceed 2000 mg per day. The maximum course of treatment is a week. You can take 1000 mg at a time, 4000 mg per day, 28000 mg per week.

children

Despite the toxicity of high doses to the kidneys and liver, the drug is one of the safest and most effective analgesics for children. Paracetamol is part of the well-known drug "Panadol".

Children's doses depend on age, weight:

10 mg per kilogram of weight from birth to three months;
60-120 mg - 3 months - 1 year;
125-250 mg - 1-5 years;
250-500 mg - 6-12 years.

Children are supposed to give medicine 4 times a day, keeping 4 hours between doses. Long course - 3 days. Do not give paracetamol to a child if he has not eaten anything for a long time. Otherwise, there is a possibility of poisoning.

Tablets are taken during, after meals, washed down with plenty of water.

Overdose

An increase in the standard dose will cause intoxication, subsequent malfunctions internal organs. Most often, poisoning occurs due to self-medication. Frequent use of paracetamol with or without reason, based on the false idea of its absolute harmlessness, will lead to health problems. The doctor will establish an accurate diagnosis and a safe dose.

In adults

Paracetamol overdose symptoms come in waves. Intoxication goes through phases.

Acute stage - begins 2 hours after taking the medicine, lasts a day. There are no specific signs. General symptoms:

Nausea;
Weakness;
Headache;
Diarrhea;
Pain in the abdomen, extending under the right rib;
Lack of appetite;
Colic, flatulence;
increased sweating;
Dyspnea.

The patient's face is pale.

Hidden stage - the symptoms subside, but damage to the tissues of the hepatobiliary zone develops - the liver, gallbladder, ducts. Urination occurs less often, pain in the right side disturbs. Manifestations occur within 24-48 hours after an overdose.

Hepatic stage - liver lesions are pronounced symptomatically, confirmed by laboratory. The development of signs occurs within 72-96 hours after exceeding the dose:

Yellow skin, whites of the eyes, mucous membranes;
Violent pain in right side;
Complete lack of appetite;
non-stop vomiting;
swelling;

Bleeding of different locations - from the nose, gums, intestinal, others;
Tachycardia;
Oppression of consciousness, close to coma;
encephalopathy;
Convulsions close to epileptic;
Decrease, cessation of urine output.

The person is disoriented, sees hallucinations, delusional. A dangerous state leads to a coma. Laboratory research show an increase in bilirubin, prothrombin time. The bile component bilirubin in an increased concentration indicates the destruction of red blood cells, an increased prothrombin time indicates blood incoagulability.

The decisive stage - if the dose is not lethal, exceeded once, the symptoms are noticed and provided health care- the liver is restored. Otherwise, the patient is threatened with death from irreversible changes in the body.

Constant intake of an increased dose leads to the development of chronic intoxication. In this case, the dose is exceeded, but not so much as to cause acute poisoning.

Signs of sluggish poisoning:

poor appetite;
Periodic nausea, vomiting;
Causeless drowsiness, apathy;
Discomfort in the right side;
Pale face, skin;
Yellowness of the skin, mucous membranes;
Decreased blood glucose levels;
increased sweating;
Small hemorrhages.

The patient often has small bruises on the skin, blood vessels in the eyes burst, and nose bleeds.

Overdose in children

The rapid metabolism in the child's body facilitates the course of intoxication. Symptoms of poisoning in a child:

Weakness;
Nausea;

Vomit;
Abdominal pain;
Skin itching, rashes;
Quincke's edema.

Liver failure is rare.

Help with poisoning

Treatment of an overdose of paracetamol in adults and children begins with gastric lavage:

Drink 1.5 liters of warm water, a pale pink solution of potassium permanganate.
Induce vomiting.
Take sorbent.
Cleanse the intestines with a laxative, magnesium sulfate.

Doctors are called in such cases:

Poisoning in infants, during pregnancy, in an elderly person;
Unable to stop vomiting;
Vomit with blood;
Bleeding from any source;
A clear failure of the heart rhythm;
Hallucinations, delusions as a result of encephalopathy;
Unconscious state;
Decrease, lack of urine.

Patients in serious condition are taken to intensive care, then placed in the toxicology department.

Clinical treatment of paracetamol overdose:

Droppers of Ringer's solution, sodium chloride purify the blood;
Intravenous administration of solutions of rheopolyglucin, hemodez replenishes the mass of lost blood;
Solutions etamzilat, dicynone stop bleeding, compensate for the loss of oxygen;

Severe bleeding is stopped by surgery;
The introduction of antioxidants - vitamins C, E;
Restoration of the liver with hepatoprotectors - Karsil, Essentiale.

Acetylcysteine is an antidote that neutralizes paracetamol during the first 8 hours after an overdose.

Paracetamol poisoning affects all organs. In severe cases, hemodialysis is prescribed. During recovery, the patient must follow a diet.

Consequences of an overdose:

Renal, liver failure;
encephalopathy;
accumulation of fluid in abdominal cavity, ascites;
pancreatitis;
Decreased blood clotting;
Myocarditis;
Hepatitis;
Pulmonary edema;
Coma.

Possible death.

Causes of poisoning

The lethal dose is 150 mg per kilogram of adult weight. How much it can be less or more depends on the body's resistance, metabolic rate. Taking a lethal dose at one time leads to death within a few hours.

20 tablets of 500 mg, washed down with alcohol, are fatal to humans. Without alcohol, 40 pills are lethal. Death occurs on the fifth day due to liver failure. Possible reason paracetamol overdose - a person's desire to commit suicide.

Acute intoxication occurs with a single significant excess of the dose. Self-medication is harmful. Patients expect immediate results, so they take more pills or more than necessary. When a child's fever persists, panicked parents give shock doses of medication. The norm is a decrease in temperature by 1 degree per hour.

An overdose can happen if the drug is taken to relieve pain. If they do not pass, the person drinks a few more pills. Frequent, intense headaches are unsuccessfully tried to be removed with paracetamol. But this means that another painkiller is needed. For a prescription, you need to see a doctor.

Paracetamol should not be taken with other non-steroidal anti-inflammatory drugs - ibuprofen, diclofenac. Otherwise, there will be intoxication affecting the liver and kidneys.

Paracetamol poisoning in children occurs by chance, negligence, out of curiosity. The first aid kit with medicines must be removed in a place inaccessible to the child.