Challenges in achieving a target international normalized ratio for deep vein thrombosis among HIV-infected patients with tuberculosis: a case series

Table 1 Drug interactions in patients with HIV and TB

DRUG	EFFECT ON CYTOCHROME P450
DRUG	Induce Cytochrome P450 (Decrease effect of warfarin)	Inhibit Cytochrome P450 (Increase effect of warfarin)
Rifampicin	X
Ritonavir (protease inhibitor)	X
Nevirapine	X
Isoniazid		X
Efavirenz^a	X	X
Fluconazole		X
Cotrimoxazole		X

^aEfavirenz may induce or inhibit cytochrome P450 through its action on CYP3A4 and CYP2C9 respectively

ISSN: 2052-1839