Acetylsalicylic acid - instructions for use, dose, side effects, contraindications

The drug has analgesic, antipyretic anti-inflammatory effect, which is due to inhibition of enzymes cyclooxygenases involved in the synthesis of prostaglandins. Acetylsalicylic acid inhibits platelet aggregation by blocking the synthesis of thromboxane A₂.

Pharmacokinetics:

At intake the absorption is complete.During absorption, it undergoes systemic elimination in the intestinal wall and in the liver (deacetylated). The resorbed part is quickly hydrolyzed by special esterases, therefore T1 / 2 - no more than 15-20 minutes.

In the body it circulates (75-90% in association with albumin) and is distributed in tissues as an anion of salicylic acid.

TSmah -2 h. The serum salicylate level is very variable. Salicylates easily penetrate into many tissues and body fluids, including. in spinal, peritoneal and synovial fluid. Penetration into the joint cavity is accelerated in the presence of hyperemia and edema and slows down in the proliferative phase of inflammation. In small amounts, salicylates are found in the brain tissue, traces - in bile, sweat, feces. When acidosis occurs, most of the salicylic acid is converted to a non-ionized acid that penetrates well into the tissue, including. in the brain. Rapidly passes through the placenta, in small quantities is excreted in breast milk.

Metabolized mainly in the liver with the formation of 4 metabolites, found in many tissues and urine.

It is excreted mainly by active secretion in the renal tubules in unchanged form (60%) and in the form of metabolites.Removal of unchanged salicylate depends on the pH of the urine (with alkalinization of urine ionization of salicylates increases, their reabsorption worsens and the excretion increases significantly). The rate of excretion depends on the dose: when taking small doses of T1 / 2 2-3 hours, with an increase in the dose may increase to 15-30 hours.

Indications:

Symptomatic treatment of pain syndrome: headache (including abstinence syndrome), toothache, sore throat, back and muscle pain, joint pain, menstruation pain.

The raised temperature of a body at cold and other infectious-inflammatory diseases (at adults and children is more senior 15 years).

Contraindications:

- Hypersensitivity to acetylsalicylic acid and other NSAIDs or other components of the drug;

- erosive and ulcerative lesions of the gastrointestinal tract (in the phase of exacerbation); hemorrhagic diathesis;

- combined use of methotrexate in a dose of 15 mg per week or more;

- a combination of bronchial asthma, recurrent nasal polyposis and paranasal sinuses and intolerance to acetylsalicylic acid;

- pregnancy (I and III trimester), the period of breastfeeding;

- children under 3 years for tablets of 250 mg, up to 6 years for tablets of 500 mg.

The drug is not prescribed for children under 15 with acute respiratory infections caused by viral infections, because of the risk of developing Reye's syndrome (encephalopathy and acute fatty liver disease with acute development of liver failure).

Carefully:With concomitant therapy with anticoagulants, gout, peptic ulcer and / or duodenal ulcer (in the anamnesis), including chronic or recurrent peptic ulcer disease, or episodes of gastrointestinal bleeding; renal and / or hepatic insufficiency, deficiency of glucose-6-phosphate dehydrogenase; hyperuricemia, bronchial asthma, chronic obstructive pulmonary disease, hay fever, nasal polyposis, drug allergy, concomitant use of methotrexate at a dose of 15 mg / week, pregnancy (II trimester).

Pregnancy and lactation:

If you need to use the drug during lactation, breastfeeding should be discontinued.

Dosing and Administration:

Inside, adults and children over 12 years of age: single dose is 0.25-0.5 g,the maximum single dose - 1.0 g (2 tablets of 0.5 g), the maximum daily - 3.0 g (6 tablets of 0.5 g), a single dose, if necessary, can be taken 3-4 times a day at intervals not less than 4 hours.

Children, except for acute respiratory infections caused by viral infections, because of the risk of developing Reye's syndrome (encephalopathy and acute fatty liver disease with acute development of liver failure), a single dose for children aged 3 years is 0.125 g (1/2 tablet 250 mg), starting from the age of 6, can be prescribed in tablets of 0.25 g per reception.

Mode of application: The drug should be taken after meals, washed down with water, milk or alkaline mineral water.

Frequency and time of reception: a single dose, if necessary, can be taken 3-4 times a day with an interval of at least 4 hours. Regular adherence to the regimen allows to avoid a sharp rise in temperature and reduce the intensity of the pain syndrome.

The duration of treatment (without consulting a doctor) should not exceed 7 days when prescribed as an anesthetic and more than 3 days - as an antipyretic.

Side effects:

From the gastrointestinal tract: pain in the abdomen, heartburn, nausea, vomiting, obvious (vomiting with blood, tarry stools) or hidden signs of gastrointestinal bleeding, which can lead to iron deficiency anemia, erosive and ulcerative lesions (including perforation) of the gastrointestinal tract, single cases - violations of the liver (increased liver transaminases).

From the central nervous system: dizziness, tinnitus (usually are signs of an overdose).

On the part of the hematopoiesis system: increased risk of bleeding, which is a consequence of the effect of acetylsalicylic acid on platelet aggregation.

Allergic reactions: skin rash, anaphylactic reactions, bronchospasm, angioedema.

When such symptoms appear, it is recommended to stop taking the drug and immediately consult a doctor.

Overdose:

Symptoms

Overdose of moderate severity: nausea, vomiting, tinnitus, hearing impairment, headache, dizziness and confusion. These symptoms occur with a decrease in the dose of the drug.

Severe overdose: fever, hyperventilation, ketoacidosis, respiratory alkalosis, metabolic acidosis, coma, cardiogenic shock, respiratory failure, severe hypoglycemia.

Treatment: hospitalization, gastric lavage, reception of activated charcoal, monitoring of acid-base balance, alkaline diuresis in order to obtain a urine pH between 7.5-8 (forced alkaline diuresis is achieved if the concentration of salicylate in the blood plasma is more than 500 mg / l ( 3.6 mmol / L) in adults or 300 mg / l (2.2 mmol / l) in children), hemodialysis, fluid loss compensation, symptomatic therapy.

Interaction:

Joint application:

- with methotrexate at a dose of 15 mg per week or more: the hemolytic cytotoxicity of methotrexate is increased (the renal clearance of methotrexate and methotrexate is replaced by salicylates in association with blood plasma proteins);

- with anticoagulants, for example, heparin: increased risk of bleeding due to inhibition of platelet function, damage to the mucosa of the gastrointestinal tract, displacement of anticoagulants (oral) from the connection with blood plasma proteins;

- with other non-steroidal anti-inflammatory drugs: as a result of synergistic interaction, the risk of ulceration and bleeding of the stomach increases;

- with uricosuric medicines, for example benzbromarone: reduces the uricosuric effect;

- with digoxin: the concentration of digoxin is increased due to decreased renal excretion;

- with hypoglycemic drugs, for example insulin: increased hypoglycemic effect of hypoglycemic drugs due to hypoglycemic effect of acetylsalicylic acid;

- with preparations of thrombolytics group: the risk of bleeding increases;

- with systemic glucocorticosteroids, excluding hydrocortisone, used as a substitute therapy for Addison's disease when using glucocorticosteroids, the level of salicylates in the blood decreases due to an increase in the excretion of the latter;

- with inhibitors of the angiotensin-converting enzyme: the glomerular filtration decreases due to the inhibition of prostaglandins and, as a consequence, the antihypertensive effect decreases;

- with valproic acid: the toxicity of valproic acid increases;

- with ethanol (alcoholic beverages): the risk of damaging effect on the mucosa of the gastrointestinal tract increases and the risk of gastrointestinal bleeding increases,

- enhances the effects of narcotic analgesics, thrombolytic agents and platelet aggregation inhibitors, sulfonamides (including co-trimoxazole);

- increases the concentration of barbiturates, lithium salts in plasma;

- antacids containing magnesium and / or aluminum slow down and worsen the absorption of acetylsalicylic acid;

- Myelotoxic drugs increase the manifestation of hematotoxicity of the drug.

Special instructions:

Acetylsalicylic acid can cause bronchospasm, an attack of bronchial asthma or other hypersensitivity reactions. Risk factors are the presence of bronchial asthma, polyps of the nose, fever, chronic bronchopulmonary diseases, cases of allergy in the anamnesis (allergic rhinitis, rashes on the skin). Acetylsalicylic acid can increase the tendency to bleeding, which is due to its inhibitory effect on platelet aggregation. This should be taken into account when necessary surgical interventions, including such minor interventions as tooth extraction.Before surgery, to reduce bleeding during surgery and in the post-operation period, you should cancel taking the drug for 5-7 days and inform the doctor.

Children should not be prescribed drugs containing acetylsalicylic acid, because in the case of a viral infection, the risk of developing Reye syndrome increases. Symptoms of Reye's syndrome include prolonged vomiting, acute encephalopathy, and enlargement of the liver.

In the treatment of vascular diseases, the daily dose of acetylsalicylic acid is 75 to 300 mg.

Acetylsalicylic acid reduces the excretion of uric acid from the body, which can cause an acute attack of gout in predisposed patients.

Effect on the ability to drive transp. cf. and fur:

There was no evidence of the effect of drug administration on vehicle management and other mechanisms.

Form release / dosage:

Tablets of 250 mg and 500 mg.

Packaging:

For 10 tablets in a contiguous cell-free or cell pack.

1 or 2 contour squares with instructions are placed in a cardboard pack.

Contour-cell and contour-less cells with equal number of instructions for use placedirectly into the group package.

Storage conditions:

Store in a dry place at a temperature of no higher than 25 ° C. Keep out of the reach of children.

Shelf life:

4 years. Do not use after the time specified on the package.

Terms of leave from pharmacies:Without recipe

Registration number:P N001190 / 01

Date of registration:10.09.2008 / 20.04.2015

Expiration Date:Unlimited

The owner of the registration certificate:TATHIMFARMPREPARATY, JSC TATHIMFARMPREPARATY, JSC Russia

Manufacturer: & nbsp

TATHIMFARMPREPARATY, JSC Russia

Information update date: & nbsp02.10.2017

Illustrated instructions

Instructions

Acetylsalicylic acid (Acetylsalicylic acid)