Total (number of patients)	39
Men	24
Women	15
Age (y)
Mean	33.6
Range	21 - 45
Patients with
Hepatitis C Ab+	39/39 (100%)
Hepatitis C PCR+	19/39 (49%)
HBsAg+	8/39 (20.5%)
CD4+ count (cells/µL)
Mean	224
Range	10 - 1515
HIV RNA level (copies/mL)
Mean	225,265 (5.35 log10)
Range	1118 - 1,194,828 (3.04 - 6.09 log10)

Drug	Effect on methadone	Presumed mechanism of action	Data	Reference
Carbamazepine	Reduced	Induction of CYP-450	Clinical only	21
Phenytoin	Reduced	Induction of CYP-450	Clinical only	21 - 24
Valproic acid	No effect		Clinical only	24
Barbiturates	Reduced	Induction of CYP-450	Clinical only	25
Fluvoxamine	Increased	Inhibition of CYP-450	Clinical and PK	26, 27
Fluoxetine	Increased	Inhibition of CYP-450	Clinical and PK	28, 29
Cimetidine	Increased	Inhibition of CYP-450	Clinical only	30, 31
Fluconazole	Increased	Inhibition of CYP-450	Clinical and PK	32
Rifampicin	Reduced	Induction of CYP-450	Clinical and PK	33 - 36
Nevirapine	Reduced	Induction of CYP-450	Clinical and limited PK	19, 37 - 39
Efavirenz	Reduced	Induction of CYP-450	Clinical	20, 40
Ritonavir	Increased	Inhibition of CYP-450	Clinical and limited PK	41, 42
Nelfinavir	Reduced	??Induction of CYP-450	Clinical and PK	43, 44
Lopinavir/ritonavir	Reduced	??Induction of CYP-450 or plasma protein binding effects	Clinical and PK	45
Zidovudine	Reduced zidovudine*	Inhibition of intracellular phosphorylation	Limited clinical and PK	46, 47
Didanosine	Reduced didanosine*	Inhibition of intracellular phosphorylation	Limited clinical and PK	48

CYP-450, cytochrome P-450; PK, pharmacokinetic.
*No alteration in the pharmacokinetics of methadone, but an interaction with the intracellular pharmacokinetics of the nucleoside analogue.