Stimulants of microsomal oxidation in the liver (phenytoin, ethanol, barbiturates, rifampicin, fennylbutazone, tricyclic antidepressants) increase the production of hydroxylated active metabolites of paracetamol, which makes it possible to develop severe intoxication with small overdoses. Paracetamol enhances the effects of MAO inhibitors, sedatives, ethanol. With simultaneous admission with antidepressants, antiparkinsonian antipsychotic drugs, phenothiazine derivatives - the risk of urine retention, dry mouth, constipation increases.
Phenylephrine reduces the hypotensive effect of guanethidine.
Guanethidine increases alpha-adrenostimulating effect, and tricyclic antidepressants - sympathomimetic effects of phenylephrine.
Glucocorticosteroids increase the risk of developing glaucoma. Paracetamol reduces the effectiveness of diuretic drugs.
Metoclopramide, domperidone increase the rate of absorption of paracetamol, and colestramine reduces.
Vitamin C increases the absorption of penicillin, iron, reduces the effect of heparin and indirect anticoagulants, increases the risk of cristallouria in the treatment of salicylates. Absorption of vitamin C decreases with simultaneous use with oral contraceptives.
Vitamin C slows the excretion of kidney acids, reduces the reabsorption of drugs that have an alkaline reaction (including alkaloids).
Vitamin C in combination with deferoxamine increases the toxic effect of iron on tissues (especially on the heart, causing the development of heart failure), the administration of preparations containing ascorbic kshhotu is carried out after determining the concentration deferoxamine and the determination of iron excretion, not earlier than 1-2 hours after the infusion of deferoxamine.