Pharmacokinetic interactions between antiretroviral drugs and herbal medicines

Abstract

Antiretroviral therapy has improved the prognosis of patients with human immunodeficiency virus (HIV) infection (Palella et al, 1998). Currently, antiretroviral therapy is the only treatment that has demonstrated efficacy for HIV. However, herbal medicines are widely used by HIV patients to complement conventional therapy. In a cross-sectional study in the UK, 61% of patients on antiretroviral therapy had used herbal medicines or supplements (Ladenheim et al, 2008) while in a South African study, 30% of patients admitted herbal medicine use (Peltzer et al, 2008). In western countries, commonly used herbal medicines include garlic, echinacea, aloe, St John’s wort and ginseng. These remedies are widely available and accessible without prescription in many countries. Therefore, cotreatment with antiretroviral therapy may occur, even without the knowledge of HIV clinicians (Peltzer et al, 2008).