PrEP Most Common Side Effects and How to Best Manage Them
PrEP or pre-exposure prophylaxis refers to the use of antiretroviral medications by uninfected individuals to reduce their risk of contracting HIV. Large clinical trials have demonstrated the effectiveness of PrEP on preventing new infections when used by people at high risk of being infected by the virus. Most of these studies have been conducted using Truvada (emtricitabine/tenofovir disoproxil fumarate), which is currently the only combination regimen approved by the FDA and recommended by the World Health Organization.
HIV/AIDS is a major public health concern; it has claimed over 35 million lives since its discovery. While various management options and prevention methods have been implemented through the years, not all of them are accessible. Majority of patients and HIV-negative individuals may not even know they exist. For those who are aware of the availability of HIV medications and prophylaxis regimens, only a few will seek treatment. The relatively high cost of HIV medications is one of their main concerns. Potential side effects are another issue that deters high-risk population groups (e.g. injection drug users) from considering antiretroviral meds. Side effects affect compliance and can lead to discontinuation of treatment and drug resistance.
Adverse effects and toxicities
TDF/FTC (Truvada) is the drug of choice for PrEP. The two fixed-dose drugs it contain are proven potent against HIV and have fewer side effects compared to other regimens. But it doesn’t mean it’s as safe as common OTC drugs like Paracetamol. It is a prescription drug for a reason: it interacts with other medications and can cause toxicities when used for long term. However, some patients also reported not having any side effects at all or experiencing mild symptoms only at the first few days of taking PrEP. A short course of Truvada may not cause serious effects, but if you need to take the drug for long term, you must be aware of the life-threatening toxicities associated with its use.
- Abdominal pain
Other adverse events:
- Weight loss
- Shortness of breath
- Muscle pain
Among those listed above, nausea and diarrhea are the most frequently reported adverse effects. At least 1 in 10 people may experience these symptoms, but they usually resolve after the first month of treatment.
Managing side effects
Nausea and vomiting – To prevent nausea and vomiting try to eat smaller meals and avoid spicy food. If it persists, ask your doctor about anti-emetics that is safe to take alongside your PrEP meds. These drugs block the brain receptors that signals the need to vomit. However, these drugs may also have their own side effects, such as sedation or drowsiness. If you are prescribed with an anti-emetic, take it at least 30–45 minutes before Truvada. Some of the most commonly prescribed drugs to control nausea and vomiting include granisetron (Kytril), ondansetron (Zofran), and metoclopramide (Raglan). Below are other recommendations in managing nausea and vomiting:
- Ginger capsules or other ginger-related food and beverages have been proven effective for pregnancy-related and drug-related nausea.
- Proton pump inhibitors or H2 antagonists may help treat nausea and vomiting secondary to acid reflux or gastritis
- Try to breathe deeply and slowly when you feel nauseated
- Some people use acupressure bands or sea-bands on their forearms to alleviate nausea
Diarrhea – Loose watery stools that are not infection-related usually resolve after a few days or weeks. It’s important to hydrate yourself and eat high-fiber food to prevent dehydration while having diarrhea. For symptomatic treatments, your doctor may prescribe one of the following:
- Over-the-counter anti-motility agents such as loperamide (Imodium) or atropine diphenoxylate (Lomotil). Take two tablets for each bowel movement but do not exceed 8 tablets per day.
- Calcium supplements at 500mg twice or thrice a day may decrease diarrhea attacks in some patients
- Psyllium (Metamucil) is a soluble fiber that may help reduce diarrhea by creating bulky stools and slowing peristalsis (contraction of the digestive tract)
- Pancrelipase is made of pancreatic enzymes and they may help in cases of chronic diarrhea caused by malabsorption
Patients with diarrhea must be encouraged to take soft, easily digestible food that are high in fiber such as rice, bananas, wheat, boiled vegetables, potatoes, soup, and crackers. Sodas, caffeinated beverages, alcoholic drinks, and dairy products must be avoided. If you experience other signs and symptoms while taking PrEP, consult your doctor right away. Do not self-medicate, as there are many drugs that triggers serious interactions with antiretroviral medications.