Active ingredient: Aminosalicylic Acid - Brands, Medical Use, Clinical Data

Brands, Medical Use, Clinical Data

Drug Category

• Antituberculosis Agents

Dosage Forms

• Packet of coated granules

Brands / Synonyms

Amino-Pas; Aminopar; Aminosalicylate Sodium; Aminox; Apacil; Apas; Deapasil; Entepas; Ferrosan; Gabbropas; Hellipidyl; Kyselina P-Aminosalicylova; Neopasalate; Osacyl; P-Aminosalicylic Acid; Pamacyl; Pamisyl; Para-Amino Salicylic Acid; Para-Pas; Paramycin; Parasal; Parasalicil; Parasalindon; PAS; PAS-C; Pasa; Pasalon; Pasara; Pascorbic; Pasdium; Pasem; Paser; PASK; Pasmed; Pasnodia; Pasolac; Propasa; Rezipas; Sanipirol-4; Sanipriol-4

Indications

For the treatment of tuberculosis

Pharmacology

Aminosalicylic acid is an anti-mycobacterial agent used with other anti-tuberculosis drugs (most often isoniazid) for the treatment of all forms of active tuberculosis due to susceptible strains of tubercle bacilli. The two major considerations in the clinical pharmacology of aminosalicylic acid are the prompt production of a toxic inactive metabolite under acid conditions and the short serum half life of one hour for the free drug. Aminosalicylic acid is bacteriostatic against Mycobacterium tuberculosis (prevents the multiplying of bacteria without destroying them). It also inhibits the onset of bacterial resistance to streptomycin and isoniazid.

Mechanism of Action

There are two mechanisms responsible for aminosalicylic acid's bacteriostatic action against Mycobacterium tuberculosis. Firstly, aminosalicylic acid inhibits folic acid synthesis (without potentiation with antifolic compounds). The binding of para-aminobenzoic acid to pteridine synthetase acts as the first step in folic acid synthesis. Aminosalicylic acid binds pteridine synthetase with greater affinity than para-aminobenzoic acid, effectively inhibiting the synthesis of folic acid. As bacteria are unable to use external sources of folic acid, cell growth and multiplication slows. Secondly, aminosalicylic acid may inhibit the synthesis of the cell wall component, mycobactin, thus reducing iron uptake by M. tuberculosis.

Absorption

Not Available

Toxicity

LD₅₀=4 gm/kg (orally in mice); LD₅₀=3650 mg/kg (orally in rabbits)

Biotrnasformation / Drug Metabolism

Not Available

Contraindications

Patients with hypersensitivity to any component of this medication should not receive aminosalicylic acid. Patients with severe renal disease will accumulate aminosalicylic acid and its acetyl metabolite but will continue to acetylate, thus leading exclusively to the inactive acetylated form; deacetylation, if any, is not significant. In addition, patients with end stage renal disease should not receive aminosalicylic acid.

Drug Interactions

Aminosalicylic acid may decrease the amount of digoxin (Lanoxin, Lanoxicaps) that gets absorbed into your body. In the case that you are taking digoxin while taking aminosalicylic acid, higher doses of digoxin may be needed. Aminosalicylic acid may also decrease the absorption of vitamin B12, which can lead to a deficiency. Therefore you may need to take a vitamin B12 supplement while taking aminosalicylic acid.