Appendix XIII: Interactions Between HIV-Related Medications and Psychotropic Medications

Updated April 2010

Table 1: Significant Interactions Between Antiretroviral Therapy and Psychotropic Medications: Contraindicated Combinations and Agents to Be Used With Caution*

Medication	Contraindicated	Use With Caution	Comments
Atazanavir (Reyataz)	Midazolam Triazolam Pimozide	Carbamazepine Phenobarbital Phenytoin	• Midazolam and triazolam levels may be significantly increased with concurrent PI use. • Carbamazepine, phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.
Darunavir (Prezista)	Midazolam Triazolam Pimozide	Carbamazepine Phenobarbital Phenytoin	• Midazolam and triazolam levels may be significantly increased with concurrent PI use. • Carbamazepine, phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of CYP450 system; consider alternative anticonvulsant.
Delavirdine (Rescriptor)	Midazolam Triazolam Pimozide	Carbamazepine Phenobarbital Phenytoin	• Midazolam and triazolam levels may be significantly increased with concurrent use; avoid combination.
Efavirenz (Sustiva)	Midazolam Triazolam	Pimozide Carbamazepine Phenobarbital Phenytoin	• Based on in vitro data, midazolam and triazolam concentrations may be significantly increased with co-administration, but in vivo, a reduction in midazolam is expected; avoid combination. • Efavirenz may increase pimozide levels; monitor closely for toxicity. • Carbamazepine, phenobarbital, and phenytoin may reduce EFV drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.
Etravirine (Intelence)	Carbamazepine Phenobarbital Phenytoin		• Carbamazepine, phenobarbital, and phenytoin may significantly reduce ETR drug concentrations due to induction of the CYP450 system; do not use.
Fosamprenavir (Lexiva)	Midazolam Triazolam Pimozide	Tricyclic antidepressants Carbamazepine Phenobarbital Phenytoin	• Midazolam, triazolam, and pimozide levels may be significantly increased with concurrent PI use. • Monitor tricyclic antidepressant therapy closely for toxicity. • Carbamazepine, phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.
Indinavir (Crixivan)	Midazolam Triazolam Pimozide	Carbamazepine Phenobarbital Phenytoin	• Midazolam, triazolam, and pimozide levels may be significantly increased with concurrent PI use. • Carbamazepine, phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.
Lopinavir/ ritonavir (Kaletra)	Midazolam Triazolam Pimozide	Carbamazepine Olanzapine Phenobarbital Phenytoin	• Midazolam, triazolam, and pimozide levels may be significantly increased with concurrent PI use. • Lopinavir/ritonavir may reduce olanzapine levels. • Carbamazepine, phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.
Maraviroc (Selzentry)	None	Carbamazepine Phenobarbital Phenytoin	• Carbamazepine and phenobarbital may increase maraviroc metabolism, leading to loss of virologic response, and possible resistance to maraviroc. Increase maraviroc dose to 600 mg twice daily with co-administration.
Nelfinavir (Viracept)	Midazolam Triazolam Pimozide	Carbamazepine Phenobarbital Phenytoin	• Midazolam and triazolam levels may be significantly increased with concurrent PI use. • Carbamazepine, phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.
Nevirapine (Viramune)	None	Carbamazepine Phenobarbital Phenytoin	• Potential for interaction with carbamazepine is unknown. Use with caution and consider monitoring carbamazepine levels.
Raltegravir (Isentress)	None	Phenobarbital Phenytoin	• Phenobarbital and phenytoin co-administration may significantly decrease raltegravir serum concentrations.
Ritonavir (Norvir)	Midazolam Triazolam Pimozide	Alprazolam, carbamazepine, clorazepate, diazepam, estazolam, flurazepam, methamphetamine, nefazodone, olanzapine, perphenazine, phenobarbital, phenytoin, risperidone, trazadone, selective serotonin re-uptake inhibitors (SSRIs), thioridazine, zolpidem	• Midazolam, triazolam, and pimozide levels may be significantly increased with concurrent PI use. • Due to the complex nature of ritonavir metabolism, increased or decreased levels of psychotropic agents may occur. Monitor patients closely when changing psychotropic agents or adding ritonavir. • Monitor desipramine levels when used with ritonavir. • Ritonavir may reduce olanzapine levels. • Carbamazepine, phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.
Saquinavir (Invirase)	Midazolam Triazolam Pimozide	Carbamazepine Phenobarbital Phenytoin	• Midazolam and triazolam levels may be significantly increased with concurrent PI use. • Carbamazepine, phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.
Tipranavir (Aptivus)	Midazolam Triazolam Pimozide	Olanzaping Mirtazapine Nefazadone Carbamazepine Phenobarbital Phenytoin	• Midazolam and triazolam levels may be significantly increased with concurrent PI use. • Carbamazepine phenobarbital, and phenytoin may reduce PI drug concentrations due to induction of the CYP450 system; consider alternative anticonvulsant.

* Tricyclic antidepressants should be used with caution with all boosted PIs.