Antibiotic, Antifungal, Antiviral Drugs

Pyrazinamide, a derivative of niacinamide, is a synthetic antituberculosis agent. Pyrazinamide is used in conjunction with other antituberculosis agents in the treatment of clinical tuberculosis.

Isoniazid usually is administered orally. The drug may be given by IM injection when oral therapy is not possible. The fixed-combination preparation containing isoniazid and rifampin (Rifamate®) and the fixed-combination preparation containing isoniazid, rifampin, and pyrazinamide (Rifater®) should be given either 1 hour before or 2 hours after a meal; the manufacturer states that Rifater® should be given with a full glass of water.

Peripheral neuritis, usually preceded by paresthesia of the feet and hands, is the most common adverse effect of isoniazid and occurs most frequently in malnourished patients and those predisposed to neuritis (e.g., alcoholics, diabetics). Rarely, other adverse nervous system effects have also occurred including seizures, toxic encephalopathy, muscle twitching, ataxia, stupor, tinnitus, euphoria, memory impairment, separation of ideas and reality, loss of self-control, dizziness, and toxic psychosis. Neurotoxic effects may be prevented or relieved by the administration of 10-50 mg of pyridoxine hydrochloride daily during isoniazid therapy, and pyridoxine should be administered in malnourished patients, pregnant women, and those predisposed to neuritis (e.g., HIV-infected individuals).

Isoniazid is used in conjunction with other antituberculosis agents in the treatment of clinical tuberculosis.

Cycloserine, a structural analog of the amino acid d-alanine, is an antituberculosis antibiotic. Cycloserine is used in conjunction with other antituberculosis agents in the treatment of clinical tuberculosis.

Capreomycin, a polypeptide antibiotic complex of 4 microbiologically active components, is an antituberculosis agent. Capreomycin is used in conjunction with other antituberculosis agents in the treatment of clinical tuberculosis.

Aminosalicylic acid is used in conjunction with other antituberculosis agents in the treatment of clinical tuberculosis. The drug is designated an orphan drug by the US Food and Drug Administration (FDA) for use in the treatment of tuberculosis. These regimens have a minimum duration of 6 months (26 weeks), and consist of an initial intensive phase (2 months) and a continuation phase (usually either 4 or 7 months). Aminosalicylic acid is considered a second-line antituberculosis agent for use in these regimens.

Antituberculosis agents are antibiotics and synthetic anti-infectives used in the treatment of tuberculosis and other diseases caused by organisms of the genus Mycobacterium. Isoniazid, rifampin, ethambutol, and pyrazinamide are the drugs used most frequently in the treatment of tuberculosis and are considered first-line agents for use in antituberculosis regimens.