Side Effects & Interaction
Side Effects
Most people who take PrEP do not experience any serious or long-term side effects. However, some people taking PrEP do experience side effects.
The most common PrEP side effects include:
Diarrhea
Nausea
Vomiting
Dizziness
Headache
These are generally short-lived and pass within a few weeks of starting PrEP.
Less common but more serious side effects of PrEP can include problems with your kidney function, liver function, and bone mineral density. Those with Hepatitis B can also experience flareups of the disease while taking PrEP.
To ensure any side effects are identified, monitored, or addressed, it’s important to discuss any side effects with your healthcare provider and to attend all follow-up screenings and appointments.
A full list of PrEP side effects can be found here.
Interactions
Recreational Drugs: There are no known interactions between PrEP and most known recreational drugs, though some recreational drugs may impact medication adherence (i.e. someone forgetting to take a dose).
If you take PrEP while using drugs or alcohol, you may want to consider some of the adherence tips explored in the regimen and adherence section on this page.
Prescription Medications: There are few cases of dangerous interactions between PrEP and other medications. If you take medications with didanosine, or take Reyataz, Kaletra, Prezista, HARVONI, EPCLUSA, or VOSEVITM, share this information with your healthcare provider as you may need to be followed more closely while taking PrEP (Gilead).
OTC Medication: People using PrEP should use non-steroidal anti-inflammatory medications (NSAIDS) with caution due to possible kidney injury.
PrEP is safe to take while taking contraceptives and during pregnancy.
PrEP is safe to take during hormone therapy.