You also shouldn’t take Truvada with drugs containing lamivudine, an
HIV drug marketed under the brand name Epivir. If you’re HIV-negative, you’re most likely not taking these, but you should have the information. And if your partner is positive, no, you can’t trade drugs with each other — different ones are right for different people, and Truvada is the only one to date approved by government regulators for HIV prevention.