Treatment of Mycobacterial infections Flashcards
Isoniazid, Rifampin, Pyrazinamide and Ethambutol are first line drugs for this condition
Tuberculosis
First line drug for tuberculosis that inhibits lipid (mycolic acid) synthesis required for cell wall integrity
Isoniazid
MOA of Isoniazid
Inhibits mycolic acid synthesis required for cell wall integrity
Isoniazid is inactivated by genetically determined ______
Acetylation
(Acetyl isoniazid may be converted to acetyl hydrazide, then to a hepatotoxic metabolite)
Tuberculosis drug that is inactivated by genetically determined acetylation
Isoniazid
Neurotoxicity from Isoniazid may be minimized by administration of this
Pyridoxine (vit b6)
Pyridoxine (B6) may minimize this adverse effect of Isoniazid
Neurotoxicity
Pyridoxine (B6) may minimize nephrotoxicity of this tuberculosis drug
Isoniazid
High acetylators have higher risk of this adverse effect of Isoniazid
Hepatotoxicity
Isoniazid use should be avoided if there is a five fold increase in this in normal individuals or three fold increase in patients with symptoms of hepatitis
Serum aspartate aminotransferase
Neurotoxicity, hepatotoxicity, and hemolysis in patients with G6PD deficiency are adverse effects of this tuberculosis drug
Isoniazid
Primary toxicity of Ethionamide
Neurological disruption
Tuberculosis drug with neurological disruption as a primary toxicity
Ethionamide
Tuberculosis drug that inhibits arabinogalactan polymerization by inhibition of arabinosyl transferase, thereby disrupting cell wall synthesis
Ethambutol
Ethambutol inhibits this enzyme
Arabinosyl transferase
thus inhibits arabinogalactan polymerization
Retrobulbar neuritis (visual defects that are usually reversible, including loss of central vision, impaired red/green discrimination, and constriction of peripheral vision) is a characteristic adverse effect of this tuberculosis drug
Ethambutol
Primary adverse effect of Ethambutol
Retrobulbar neuritis (visual defects)
MOA of rifamycins
Inhibit DNA-dep RNA pol
Tuberculosis drug that inhibits DNA-dep RNA pol
Rifamycin
Tuberculosis drug that can induce microsomal enzymes systems (high risk of drug interactions)
Rifamycin
Tuberculosis drug where half life will fall during early stages of therapy due to autoinduction
Rifamycin
Tuberculosis drug that has increased risk of hepatotoxicity when given with isoniazid
Rifamycin
Tuberculosis drug with immunosuppressive effects, most common with intermittent therapy, early flu-like symptom
Rifamycin
Is Pyrazinamide safe in pregnancy?
Not recommended; effect on fetus unknown
Hepatotoxicity related to dose and duration of treatment, and Hyperuricemia are adverse effects of this tuberculosis drug
Pyrazinamide
Hyperuricemia is an adverse effect of this tuberculosis drug
Pyrazinamide
2 main adverse effects of Pyrazinamide
Hepatotoxicity
Hyperuricemia
2 Tuberculosis drugs that inhibit dihydropteroate synthase to block folate synthesis
Para-Aminosalicylic acid and Dapsone
MOA of Para-Aminosalicylic acid
Inhibits dihydropteroate synthase to block folate synthesis
Sodium overload is a concern for this tuberculosis drug as oral preps are very high in sodium
Para-Aminosalicylic acid
This is a concern with Para-Aminosalicylic acid oral preps
Sodium overload
Tuberculosis drug with similar structure to Alanine, acts as a competitive inhibitor of Alanine racemase, blocks incorporation of D-ala into cell wall components
Cycloserine
MOA of cycloserine
Similar structure to alanine
Competitive inhibitor of alanine racemase
Blocks incorporation of D-alanine into cell wall components
2 main adverse effects of cycloserine
Neurological effects
Hemolysis in patients with G6PD deficiency
MOA of Dapsone
Inhibits folic acid synthesis by inhibiting dihydropteroate synthase
Characteristic hypersensitivity reaction of Dapsone involving fever, malaise, exfoliative dermatitis, jaundice and hepatic necrosis
Sulfone syndrome
Characteristic hypersensitivity reaction involving fever, malaise, exfoliative dermatitis, and juandice and hepatic necrosis is an adverse effect of this tuberculosis drug
Dapsone
6 month TB treatment regimen involves these 4 drugs during the intensive phase
“RIPE”
Rifamycin
Isoniazid
Pyrazinamide
Ethambutol
