Pharmacology Mnemonics - Flash Cards

Name: Pyrazinamide

Class: Antitubercular

Mech.: Bactericidal. Unknown mech.

Absorption: Well absorbed orally. Not affected by food.

Distribution: Dist. in total body water.

Metab.: Partially metabolized — hydrolyzed, hydroxylated

Excretion, t½: Glomerular filtration. 8 hrs.

Toxicity/S.E.s: Liver necrosis, hyperuricemia, nausea, vomiting, complication of diabetes management.

Utility: Used to treat TB when there is resistance to other agents. Requires 3 additional effective agents.

Special Features:

Name: Ethambutol (Myambutol)

Class: Antitubercular

Mech.: Tuberculostatic, mech. unknown, may involve inhib of mycolic acid synth.

Absorption: Well absorbed orally. Not affected by food.

Distribution:

Metab.:

Excretion, t½: Renal excretion (50% unchanged and 15% inactive metab. in 24 hr)

Toxicity/S.E.s: Few. Decreased visual acuity and ability to perceive color green (usually reversible). Gout.

Utility: Treat TB. Resistance develops is used alone. Usu. used with isoniazid.

Special Features:

Name: Rifampin (Rifadin)

Class: Antitubercular

Mech.: Inhib. of bact. DNA-dependent RNA polymerase. Resist develops rapidly.

Absorption: Orally effective

Distribution: Diffuses freely into tissues and fluids

Metab.: Liver

Excretion, t½: 30% excreted in urine (50% active). T1/2= 1.5-5 hrs. ¯ in slow acetylaters.

Toxicity/S.E.s: Low incidence. Jaundice (can be fatal). Use w/caution w/impaired liver fxn. Induces hepatic microsomal enzymes. GI distress, diarrhea, CNS complaints, hypersensitivity. Influenza-like syndrome.

Utility: Rapidly improves TB patients to non-infectious state. Always used w/other agents. Esp. useful in serious cases of TB. Asymptomatic carriers of N. meningitis, eryth-resist. Legionella pneumophila infects. DOC for prophylaxis of H. influenza meningitis.

Name: Isoniazid (INH)

Class: Antitubercular

Mech.: Tuberculostatic to resting bacilli, tuberculocidal to rapidly dividing cells. Enters cells via active uptake. Interferes w/DNA synth, glycolyis, synth of mycolic acid (unique component of mycobacteria)

Absorption: Rapidly absorbed after oral admin.

Distribution: Distributes in total body water. Retained in infected tissue.

Metab.: Acetylated in liver.

Excretion, t½: Urine. 75-90% in urine as metabolites in 24 hrs.

Toxicity/S.E.s: Direct—inactivation/depletion of pyridoxine ® peripheral neuritis (treat prophylactically w/supplemental pyridoxine). Hypersensitivity rxns. Hepatitis (can be fatal) due to toxic metabolites. Convulsions, optic neuritis, toxic encephalopathy, reversible psychotic episodes.

Utility: Most important and widely used drug for tuberculosis. Prob. w/resistance.

Special Features: Only drug approved for prophylaxis of tuberculosis.