If you’ve been prescribed efavirenz, you’re probably taking it as part of a combination pill for HIV. It’s an antiretroviral that blocks the virus from copying itself, keeping your viral load low and your immune system stronger. Most people start with a 600 mg tablet once a day, usually taken at night because it can make you feel a bit dizzy or sleepy.
The standard dose is one tablet every evening with food. Taking it with dinner helps reduce the stomach upset many users report. If you miss a dose, take it as soon as you remember—unless it’s almost time for your next pill, then just skip the missed one. Don’t double‑up; that can raise the risk of side effects.
Some people feel vivid dreams or mood changes in the first weeks. Those feelings often fade after a month, but if they linger or get worse, call your doctor. Blood tests are usually done every few months to check liver function and make sure efavirenz isn’t causing problems.
The most reported side effects are dizziness, headache, insomnia, and a rash that can be itchy or mild. A small number of users get a severe skin reaction called Stevens‑Johnson syndrome—if you see blistering, fever, or flu‑like symptoms, seek medical care right away.
Efavirenz can also affect your mental health. If you notice anxiety, depression, or thoughts of self‑harm, let a healthcare professional know immediately. Adjusting the dose or switching to another drug may be necessary.
Many people look for cheaper options on the internet. The safest approach is to use a licensed U.S. pharmacy that requires a prescription, shows clear contact info, and has a pharmacist available for questions. Check for accreditation symbols like VIPPS or NABP.
Avoid sites that promise “no prescription needed” or offer prices that seem too good to be true—those are often counterfeit. If you’re unsure, compare the pharmacy’s reviews, verify its address, and read the privacy policy.
Efavirenz mixes with a lot of other meds. St. John’s wort, certain anti‑seizure drugs, and some antibiotics can lower efavirenz levels, making it less effective. Alcohol may increase dizziness. Always list every supplement and prescription to your doctor.
Pregnant women need special attention: efavirenz is linked to birth defects when taken early in pregnancy, so doctors often switch to a different regimen if you’re planning a family.
Efavirenz works best when you stick to the schedule, watch for side effects, and use a reputable pharmacy. If anything feels off, reach out to your healthcare team—early tweaks can keep you feeling good while the medication does its job.
