When it comes to side effects of HIV medications, the gut, or gastrointestinal tract, is commonly affected. Vomiting and diarrhea are mechanisms for keeping toxins and pathogens out of the body, and medications can be recognized as toxins.

Modern  antiretrovirals are generally well tolerated, and not everyone experiences these side effects. If nausea, vomiting and diarrhea do occur, they are usually mild to moderate and tend to diminish after the first few days or weeks after starting a new medication. But if they are severe or prolonged, they can affect your health, quality of life and ability to adhere well to treatment. What’s more, vomiting and diarrhea can prevent HIV meds from being properly absorbed and doing their job.

Nausea and Vomiting

Many people with HIV who experience nausea, with or without vomiting, do so soon after starting antiretroviral treatment or switching to a new regimen. In most cases, these side effects lessen or go away completely after the first few days or weeks of treatment.

Contact your doctor if nausea is seriously affecting your ability to eat or if vomiting continues for more than a few days. Prolonged vomiting can lead to dehydration and changes in electrolyte levels, so it’s important to replace lost fluid.

Management of more severe or prolonged nausea and vomiting may include changing antiretrovirals and evaluating whether other medications you are taking could be contributing to the problem.

Medicines known as antiemetics may be used to relieve nausea and vomiting. They work by blocking receptors in the part of the brain that controls vomiting. Common antiemetics include Zofran (ondansetron), Kytril (granisetron), Anzemet (dolasetron) and Decadron (dexamethasone). Some people find that cannabis helps relieve nausea and stimulates the appetite. Two active chemicals in cannabis, THC (tetrahydrocannabinol) and CBD (cannabidiol), are available in edible products. Most states have now legalized medical marijuana, and dispensaries often have an array of products to choose from. Marinol (dronabinol), is a synthetic pharmaceutical version of THC. Not all medications are equally effective for everyone, and it may take some trial and error to figure out which ones work best for you.


Diarrhea, or loose, watery stools, may be a side effect of antiretroviral medications or a symptom of HIV itself. Immunocompromised people are more prone to food-borne pathogens, and those with a very low CD4 count are at risk for opportunistic illness that can cause diarrhea. 

When it’s a drug side effect, diarrhea typically occurs soon after starting a new medication and usually improves after a few days or weeks. 

Prolonged diarrhea can lead to dehydration and inadequate nutrition. Generally speaking, diarrhea that occurs five or more times a day, lasts for five or more consecutive days and results in five or more pounds of weight loss should be reported to a health care provider. 

Several over-the-counter drugs can help relieve diarrhea, including Imodium AD (loperamide), Kaopectate and Pepto Bismol. Metamucil is commonly used as a laxative, but its fiber content can also absorb water in the colon and help control diarrhea. Stronger prescription anti-diarrhea medications include Mytesi (crofelemer; approved specifically for people with HIV), Lomotil (diphenoxylate/atropine) and tincture of opium. Your doctor may aso prescribe medications to fight bacteria or viruses that are causing diarrhea.

Tips to Ease Nausea and Diarrhea

    • Breathe deeply and slowly when you first feel nausea.
    • Cut open a lemon and smell the fresh scent.
    • Drink clear juices and sports drinks at room temperature.
    • Eat smaller amounts of food throughout the day instead of larger meals.
    • Relax before meals, chew slowly and don’t rush your meal. 
    • Try foods and drinks that contain ginger or peppermint.
    • Try the BRATT diet: bananas, white rice, apple sauce, toast and herbal tea.
    • Avoid foods that can trigger nausea and diarrhea, including spicy foods, dairy produts, fried or fatty foods, caffeinated drinks and alcohol.
    • Try probiotics to improve your gut heath.
    • Acupressure bands (known as Sea-Bands) worn on the wrist may help control nausea.

    Last Reviewed: April 25, 2023