Shandong Zhanhua Yonghao pharmaceutical & Tech Co.,Ltd

Pre-exposure prophylaxis (PrEP): PrEP is an HIV prevention tool in which an HIV-negative person takes antiretroviral medication to reduce the risk of contracting HIV. Currently, there are three FDA-approved medications for PrEP: 

Truvada (tenofovir disoproxil fumarate/emtricitabine)
Descovy* (tenofovir alafenamide/emtricitabine)
Apretude (extended-release cabotegravir)

How does PrEP work?

PrEP only works if you take it. Data from the iPrEx trial show that daily adherence of oral PrEP reduces HIV risk between 96 percent and greater than 99 percent. Those who took four doses a week remained fully protected, and those who took two lowered their chance of getting HIV by 76 percent. Data from the HPTN 083 and HPTN 084 studies showed that long-acting injectable regimens are even more effective than PrEP pills at preventing HIV acquisition.

What about side effects?

Rates of side effects while on oral PrEP are low. Mild symptoms such as stomach cramps, headaches and loss of appetite may appear the first few weeks. Long-term use raises issues of kidney health and bone density. Health care providers should regularly test for kidney function. The most common side effect of long-lasting injectable PrEP is injection site reactions, including pain, redness or swelling. Rare but potentially serious adverse effects of injectable PrEP include hypersensitivity reactions, hepatotoxicity (liver damage) and depression.

What about drug resistance?

If you are HIV positive and start PrEP, the virus can become resistant to one or both meds in Truvada. This mutated virus is weaker and less likely to transmit. Still, it is important you are not in the window period of HIV infection when beginning PrEP.