Which of the following anti-retroviral drugs is contraindicated in pregnancy?

Ans. d (Efavirenz) (Ref. Harrison's medicine 16th ed., p 320, 1125)EFAVIRENZ# NNRTI# 600 mg qd# Not to be taken with a fatty meal# Dizziness, insomnia, rash, transaminitis# EmbryotoxicCONTRAINDICATIONS TO ABACAVIR# Allergies {It should not be taken if patient has ever had an allergic reaction to it, because it could cause another severe reaction that may result in death),# Breast-feeding,# Liver diseases,# Pregnancy.Anti-retroviral therapyReverse transcriptase inhibitorsProtease inhibitorsFusion inhibitorsAZT (Zidovudine)SaquinavirEnfuvirtideDidanosineRitonavirMirovirocZalcitabineNelfinavir StavudineAmprenavir LamivudineFosamprenavirIntegrase InhibitorEmtricitabineLopinavirRaltegnavirAbacavirAtazanavir Tenofovir Delavirdine Nevirapine Efavirenz A. Nucleoside Reverse Transcriptase Inhibitors (NRTIs)- NRTIs are generally prodrugs that are converted to active forms via phosphorylation. Prevent conversion of viral RNA into dsRNA. Mechanisms and resistance mechanisms similar. Some cross-resistance occurs. Drugs differ in toxicity profiles (major side effects are listed below) and can cause lactic acidemia.1.Zidovudine (ZDV-AZTInhibits reverse transcriptase# Used in HAART and in prophylaxis following needlesticks and to prevent maternal/fetal transmission# Bone marow suppression--dose limiting, may require transfusions2.Didanosine (ddl) # Pancreatitis (dose limiting)3.Zalcitabine (ddC) # Peripheral neuropathy4.Stavudine (c4T) # Peripheral neuropathy5.Lamivudine (3TC) # Fewer side effects - mild GI distress, headache # Also useful in treating hepatitis BB. Nonnucleoside Reverse Transcriptase Inhibitors (NNRTIs)-(Do not require metabolic activation, no cross-resistance)1.NevirapineInhibits reverse transcriptasePrevents maternal/fetal transmission2.Delavidine Major drug interactions, possible teratogen3.Efavirenz Major drug interactions, possible teratogenC. Protease Inhibitors-(Inhibition of asparate protease (HIV-1 protease); a pol gene product; prevents viral assembly)1. Indinavir2. Ritonavir3. Saquinavir4. Nelfinavir5. Amprenavir6. LiponavirInhibits asparateGI distress, hyperglycemia, hyperlipidemia, altered fat distribution, nephrolithiasis (maintain hydration, indinavir), thrombocytopenia (indinavir)D. Fusion Inhibitor1. EnfuvirtideBinds gp41, preventing fusion of viral and cellular membranes