Paracetamol overdose - symptoms and effects
Paracetamol is a drug that is available in almost every home. It is used as an antipyretic and analgesic without thinking about the danger that this seemingly harmless medicine carries with it. After all, it can be given even to children. This raises the question - is it possible to poison with paracetamol?
This medicinal substance began to actively apply from the middle of the XX century. It is part of a large number of drugs. And more and more often there are cases of overdose with paracetamol, sometimes fatal. Everyone should know how to avoid the tragic consequences, what are the signs of poisoning and what to do in an emergency. We will discuss these questions below.
What is dangerous paracetamol
Upon receipt of paracetamol in the body most of the drug enters the blood during the first two hours. The maximum concentration is reached after four hours. Paracetamol is eliminated bypassing the liver. Hazardous metabolites are formed under the action of a special (microsomal) enzyme system of the liver - cytochrome P-450. Neutralization is tripeptide - glutathione.
If a small amount of paracetamol enters the body, then the toxic products of its metabolism are bound in the liver by glutathione and excreted without causing harm. With an excess intake of the drug, glutathione reserves may not be enough, and the metabolites begin to bind to the proteins of the liver cells, which leads to their death and the appearance of symptoms of overdose with paracetamol.
Products of metabolism have a toxic effect on the kidneys, pancreas, heart and central nervous system. Contribute to the development of acidosis (pH shift in the acidic side) and depression of consciousness.
The maximum daily dose of paracetamol for an adult is 4 grams, if there is liver disease, then even less. A single intake of 7.5–10 grams leads to intoxication. Lethal is a dose of 25 grams.
Causes of paracetamol poisoning:
- attempted suicide;
- accidental use of a large dose as a result of the simultaneous use of paracetamol and the combined means in which it is present: Citramon, Pentalgin, Caffetin, Ibuklin, Theraflu, Fervex, Rinzasip;
- combination with alcohol;
- simultaneous administration of drugs that stimulate the activity of cytochrome P-450: Phenobarbital, antihistamines, hormones, etacrynic acid;
- chronic liver disease;
- long-term use of large doses of the drug.
Symptoms of Paracetamol Overdose
There are four stages of acute poisoning.
In the first stage, non-specific symptoms of paracetamol poisoning appear. General malaise, nausea and vomiting appear. Laboratory values are within normal limits.
The second stage begins in a day or a bit more from the moment of taking paracetamol. During this period, there are signs of liver damage. The severity of the condition depends on the extent of the lesion. An increase in liver enzymes is observed in the blood: AsAT and AlAT. Indicators exceed 1000 U / l.
The third stage begins after 72–96 hours. Acute necrosis (death) of the liver develops. Hemorrhages appear, hepatic encephalopathy develops, which can go into a coma. The activity of hepatic enzymes is very high and may exceed 10,000 U / l. The level of bilirubin increases, the glucose content decreases. The blood concentration of lactic acid increases, the pH of the blood decreases - acidosis develops.
Symptoms of acute liver failure:
- neuropsychiatric disorders: drowsiness, alternating motor agitation, dizziness, impaired speech, delayed thinking, general weakness progresses, hallucinations, confusion, convulsions and coma appear;
- dyspepsia: complete lack of appetite, nausea, vomiting, diarrhea;
- pain in the right hypochondrium;
- swelling and an increase in the abdomen due to fluid (ascites) appear;
- bleeding: subcutaneous hemorrhage, nosebleeds, bleeding gums;
- jaundice and fever, a precursor of coma is hypothermia (decrease in body temperature below normal);
- specific hepatic odor;
- decrease in the size of the liver;
- heart rhythm disorder;
- multiple organ failure.
Death as a result of an overdose of paracetamol may occur on the 3-5th day. Causes of death: failure of all organs and systems, bleeding, swelling of the brain or sepsis.
The fourth stage is recovery. Due to the fact that the liver has the ability to regenerate, its rapid recovery occurs. This period can take up to several weeks.
Diagnosis of poisoning
If an overdose is suspected, it is necessary to investigate the level of paracetamol in the blood. To determine the need for the use of antidote use rumak-Matthew nomogram, which allows to predict the severity of liver tissue damage.
Research is done 4 hours after the drug has entered the body. For this you need to know the exact time of poisoning. If there are no clinical manifestations and the concentration is less than 150 µg / ml, then there is no danger. With a higher content of toxic substances the risk of liver damage is very high and requires the immediate introduction of the antidote.
If the content of paracetamol is dangerous, then the levels of hepatic enzymes, bilirubin, glucose, and blood coagulation levels are monitored daily.
First aid and treatment
As in any emergency, you need to clearly know what to do when you take paracetamol overdose. If there are suspicions of taking a large dose of the drug, then the following should be done.
- Wash the stomach with plenty of water.
- Take activated charcoal, the dose of which depends on body weight, approximately 1 tablet per 10 kilogram of weight. This will prevent further absorption of the toxic substance.
- Call an ambulance.
The main antidote is acetylcysteine, which is a precursor of glutathione. As a result of its introduction, toxic products of paracetamol metabolism are neutralized and eliminated from the body. The optimal time for taking the drug is the first 8 hours.
An antidote is taken orally or as an intravenous infusion. The initial dose for oral administration (through the mouth) is 140 mg / kg of body weight. After that, every 4 hours take a dose of 2 times less. To improve the taste of the drug can be diluted in a ratio of 1: 4 juice or carbonated drink.
For infusion therapy (injections), Acetylcysteine is diluted in 200 ml of 5% glucose or saline. The initial dose is 150 mg / kg of weight, after which the treatment is continued in lower doses for 16 hours.
In light cases, you can use Methionine, which is also a source of glutathione. Is taken orally with an interval of 4 hours by 2.5 grams.
With the development of severe hepatic insufficiency, symptomatic treatment is carried out:
- detoxification therapy: plasmapheresis, hemosorption, hemodialysis;
- to improve microcirculation, metabolism, restore electrolyte balance and eliminate acidosis, solutions of glucose, albumin, reopolyglucin, hemodez are administered intravenously;
- Mannitol is administered to avoid cerebral edema against the background of infusion therapy;
- vitamin therapy: vitamins of group B, Ascorbic acid;
- for hemorrhagic syndrome, it is advisable to administer: Vikasola, aminocaproic acid, etamzilat;
- with the development of pronounced disorders of the blood coagulation function, plasma is infused;
- if such a need arises, antibiotics are prescribed;
- use oxygen inhalation to combat hypoxia.
The consequences of paracetamol overdose may be such that a liver transplant may be necessary to save a person’s life. In mild cases, the outcome is favorable. The prognosis depends on the dose of the drug, timely treatment and adequate therapy.
Features of paracetamol poisoning in children
Oddly enough, children with paracetamol poisoning manifest much more easily than adults, especially among those whose age has not reached 6 years. This is due to the peculiarities of the metabolism. For a child’s body, a dose of 150 mg / kg of weight is dangerous. Signs of liver failure are extremely rare.
The principles of assistance with paracetamol overdose in children are similar. Only the doses of the antidote and the amount of fluid administered by intravenous infusions differ. In mild cases, perhaps home treatment.
How to avoid paracetamol poisoning
Prevention in this case is very important if you do not want to feel for yourself what will happen from paracetamol overdose.
- take medication prescribed by a doctor in an acceptable dose, with an interval of at least 4 hours;
- with existing liver diseases, the dose of the drug should be reduced;
- do not combine reception of paracetamol with other drugs containing this substance, before using it is necessary to study the composition of the combined means;
- treatment with paracetamol should not exceed five days;
- avoid alcohol and drugs that increase the metabolism of paracetamol;
- medications must be out of reach of children.
Summing up, we can conclude that everything is good in moderation. Even the usual medicine can cause irreparable harm to health. You can not prescribe yourself a treatment, always seek the advice of a doctor!