|
HIVManagement.org |
|
efavirenz |
|
Detailed Prescribing Information |
|
May 2011 |
| Efavirenz = Sustiva | |
| Forms Available | 50 mg, 100mg, 200 mg capsules; 600 mg tablets |
| Dosing |
3x200 mg or 600 mg daily Usually taken at bedtime but if too much stimulation or dreaming, dosing can be done in the AM |
| Meal dependence |
High fat meals elevate Cmax of capsule by 40%
and tablets by 80% which may result in increased CNS stimulation and adverse
events. Consider initiating therapy on an empty stomach and if tolerated administer with low fat and then regular feeds. |
| Contraindication |
Pregnancy or desire to become pregnant or
inadequate birth control precautions Do not use with saquinavir as the sole protease inhibitor Midazolam, triazolam, and ergot derivatives are not to be used with Sustiva. St. John's Wort may decrease Sustiva levels and is therefore not to be used. Voriconazole should not be used with efavirenz. |
| Adverse Effects |
50% CNS stimulation including sleeplessness, confusion, nightmares: this may be debilitating over short-term or long-term 5% incidence of rash, usually mild and NONPROGRESSIVE with continued treatment Hepatitis which may be severe |
| Interactions |
Efavirenz decreases PI levels (compensate by increasing PI dosage 25-33%)
|
|
Decreases oral contraceptive pill efficacy Decreases methadone, fentanyl, imidazole antifungal drug levels Decreases warfarin efficacy Decreases voriconazole levels to subtherapeutic |
|
| Suggested lab follow-up | Liver profile at 30 days and every 2-3 months and as indicated |
| Warning | Low barrier to one-step mutation. Use only with other potent agents. |
| Sudden discontinuation of efavirenz-containing antiretroviral regimens without substitution of other potent antiretroviral or antiretroviral combination may result in prolonged subtherapeutic serum levels of nevirapine. These subtherapeutic drug levels may result in the development of mutational resistance and loss of activity for efavirenz and the NNRTI class as it exists currently (May 2004) See Usage Suggestions below for further information. | |
|
Administration Protocol |
Initiation of efavirenz: Initiate therapy during a period that is noncritical for CNS function in the patient's life (eg on a work weekend). Dosing may be suggested either immediately before bedtime or in the AM, whichever is better tolerated by the patient. Tolerance to these CNS effects (sleeplessness, nightmares, alteration of mentation, stimulation) may improve over the first two weeks of therapy. Observe dosing interactions with protease inhibitors carefully (see above) |
|
Discontinuation of efavirenz: It is recommended that when antiretrovirals are discontinued that include nevirapine and efavirenz, a potent and active protease inhibitor should be substituted first for the NNRTI. This PI substitution therapy should then be continued for 2 weeks. At that point when NNRTI serum and/or intracellular levels are essentially zero, the PI-based substitute antiretroviral therapy may be stopped. Alternatively stop the efavirenz for 5 days prior to stopping the NRTI backbone. |
|
| Complete prescribing information | http://www.sustiva.com |
| Links to Antiretroviral Sections (click on anything) |
| Nucleoside & Nucleotide Reverse Transcriptase Inhibitors (NRTI) |
| AZT | ddI | d4T | 3TC | ABC | FTC | TDF | Combivir | Trizivir | Epzicom | Truvada |
| Nonnucleoside Reverse Transcriptase Inhibitors (NNRTI) |
| efavirenz | nevirapine | delavirdine | etravirine | rilpivirine |
| Protease Inhibitors (PI) | Boosted Protease Inhibitors |
| saquinavir | indinavir | ritonavir | nelfinavir | lopinavir + ritonavir | atazanavir | fosamprenavir | tipranavir |
| Fusion Inhibitors |
| enfuvirtide |
Updated 5.22.2011