Drug Name

Mestinon (Pyridostigmine)

Pharmacological action

Acetylcholinesterase and pseudocholinesterase inhibitor. It has indirect cholinomimetic effect due to reversible inhibition of cholinesterase and potentiation of endogenous acetylcholine action. It improves neuromuscular transmission, increases tone and peristalsis of gastrointestinal tract, increases tone of bladder, bronchi, secretion of exocrine glands. It causes bradycardia, mild miosis, accommodation spasm. It has no central action.

Pharmacokinetics

Bioavailability is 8-20%, in myasthenia gravis it can be reduced to 4%. Time of reaching Cmax in plasma is 1.5-3 hours; simultaneous intake of food does not decrease bioavailability but can delay time of reaching Cmax. T1/2 is 2.5 hours. Does not penetrate through the BBB. Practically does not bind with plasma proteins. Partially metabolized in the liver to form inactive metabolites. It is excreted unchanged by the kidneys and as metabolites.

Contraindications to use

Hypersensitivity to Mestinon (Pyridostigmine); previous administration of depolarizing muscle relaxants (suxamethonium, decamethonium bromide), iritis, chronic obstructive bronchitis, bronchial asthma, mechanical bowel obstruction, biliary and urinary obstruction, spastic conditions of GIT organs, myotonia, shock in the postoperative period; Pregnancy, lactation (breast-feeding), children and adolescents under 18 years of age.

With caution: arterial hypotension, decompensated heart failure, renal failure, acute myocardial infarction, peptic ulcer, bradycardia, diabetes, parkinsonism, cholelithiasis without obstruction, urolithiasis without obstruction, conditions after GI surgery, liver failure, hyperthyroidism.

Administration during pregnancy and lactation

It is contraindicated in pregnancy and during lactation (breast-feeding).

Administration with liver dysfunction

Contraindicated for use in the obstruction of the biliary tract. Caution should be exercised when using with cholelithiasis in the absence of obstruction and in case of hepatic insufficiency.

Administration in patients with kidney dysfunction

It is contraindicated in case of obstruction of the urinary tract. Caution should be used in patients with urolithiasis without obstruction.

Administration in children

Administration in children and adolescents under 18 years of age is contraindicated.

Indications of active substances of the drug Mestinon (Pyridostigmine)

Myasthenia gravis.

Dosing regimen

Orally. Dosing regimen is established individually, depending on the severity of the disease and the response to treatment.