What is Sustiva? Uses, Dosage, Side Effects & Safety Tips

Written By Derick Mugambi Tagged As Sustiva efavirenz HIV medication antiretroviral side effects

Quick Takeaways

Sustiva is the brand name for efavirenz, an antiretroviral used in HIV‑1 treatment.
It’s taken once daily, usually at bedtime, with or without food.
Common side effects include vivid dreams, dizziness, and rash; most are mild and short‑lived.
Never combine Sustiva with certain antidepressants, rifampicin or St. John’s wort without doctor approval.
If you notice severe rash, mood changes, or liver‑related symptoms, seek medical help immediately.

How Sustiva Works and Who Should Take It

Sustiva belongs to the non‑nucleoside reverse transcriptase inhibitor (NNRTI) class. In simple terms, it blocks an enzyme that HIV needs to copy itself, slowing the virus down and giving the immune system a chance to recover. The drug is approved for use in combination with other antiretrovirals, typically as part of a fixed‑dose regimen like Atripla.

The medication is prescribed for adults and children over three years old who are newly diagnosed with HIV‑1 or who need a change in their treatment plan because of resistance or side‑effects from other drugs. It’s not meant for HIV‑2, and pregnant women should discuss risks with their provider, as efavirenz has been linked to birth defects in early studies.

For most patients, Sustiva offers a convenient once‑daily dosing schedule and has become a staple in first‑line therapy worldwide, especially in low‑ and middle‑income countries where the cost is lower than many newer agents.

Dosage and Administration

The standard adult dose is 600mg (one 600mg tablet) taken once a day, preferably at bedtime. Taking it at night helps reduce the impact of dizziness and vivid dreams, two of the most frequently reported central‑nervous‑system (CNS) effects.

For children weighing 30kg or more, the same 600mg dose is used. For smaller children, dosing is weight‑based: 10mg per kilogram of body weight, rounded to the nearest tablet strength.

Here’s a quick checklist to make sure you’re taking it correctly:

Take the tablet with a full glass of water.
If you have a sensitive stomach, you can eat a small snack, but it’s not required.
Do not split, crush, or chew the tablet; the coating is designed for slow release.
Set a daily reminder - consistency is key for keeping viral load low.
Never miss more than two doses in a row without talking to your clinician.

If you forget a dose and it’s less than 12hours before the next scheduled dose, skip the missed tablet and continue as normal. Taking a double dose to “catch up” can increase the risk of side effects.

Side Effects and Management

Most people tolerate Sustiva well, but around 30‑40% experience at least one CNS side effect during the first few weeks. The good news is that they usually improve after the body adjusts. Below is a table that summarises the most common adverse events and their typical frequency.

Side Effect	Incidence (Adults)	Management Tips
Vivid dreams / nightmares	15‑20%	Take the tablet right before sleep; avoid caffeine & alcohol late in the day.
Dizziness / light‑headedness	10‑15%	Stand up slowly; stay hydrated; if severe, talk to your doctor about dose timing.
Rash (mild to moderate)	8‑12%	Cool compresses; antihistamines if itching; seek care for widespread or blistering rash.
Depression / mood swings	5‑7%	Monitor mood daily; involve mental‑health professional early; never stop abruptly.
Elevated liver enzymes	2‑4%	Regular blood tests; avoid alcohol; report jaundice or severe fatigue.

If you develop a rash that spreads quickly, blisters, or is accompanied by fever, treat it as a medical emergency - some skin reactions can progress to Stevens‑Johnson syndrome, a rare but serious condition.

For CNS symptoms, many clinicians recommend a short “lead‑in” period where the dose is taken every other day for the first week, then switched to daily once tolerable. Always discuss any plan with your healthcare provider.

Interactions, Precautions, and FAQs

Sustiva is metabolised mainly by the liver enzyme CYP2B6. This means it can both affect and be affected by other drugs that use the same pathway. Below are the top culprits you should flag to your pharmacist or doctor:

Rifampicin (used for TB) - can lower efavirenz levels, risking treatment failure.
St. John’s wort - herbal supplement that also induces CYP enzymes, with a similar effect as rifampicin.
Some antidepressants (e.g., fluoxetine, paroxetine) - may increase efavirenz concentrations, worsening CNS side effects.
Azole antifungals (ketoconazole, fluconazole) - can raise efavirenz levels, requiring dose adjustment.

Precautions include:

Baseline and periodic liver function tests, especially if you have hepatitis B or C.
Pregnancy counseling - discuss risk‑benefit with your obstetrician.
Screening for mental‑health conditions before starting, as the drug can exacerbate depression.

FAQ

Can I take Sustiva with food? Yes, it can be taken with or without meals. A light snack at night may help reduce stomach upset.
How long does it take to see viral suppression? Most patients achieve an undetectable viral load within 8‑12 weeks if adherence is >95%.
Is it safe to drink alcohol? Moderate alcohol is generally okay, but heavy drinking can worsen liver toxicity and CNS effects.
What should I do if I miss a dose? If it’s less than 12hours until the next dose, skip the missed one. Otherwise, take it as soon as you remember, then continue with the regular schedule.
Can I switch from another NNRTI to Sustiva? Yes, but a doctor should oversee a “wash‑out” period and monitor viral load closely during the transition.

When in doubt, always reach out to your HIV specialist. They can tailor the regimen, run necessary labs, and help you navigate any side‑effect puzzle.

Next Steps & Troubleshooting

After you’ve started Sustiva, keep a simple log:

Date & time you take the tablet.
Any new symptoms (sleep changes, mood, rash).
Other medications or supplements added.

Bring this log to your follow‑up visits - it makes it easier for the clinician to spot patterns and adjust therapy quickly.

If you’re experiencing persistent side effects that interfere with daily life, ask your doctor about the possibility of switching to an integrase‑strand transfer inhibitor (INSTI) based regimen, which many patients find more tolerable.

Remember, the goal of any antiretroviral is to keep the virus suppressed forever. Consistency, open communication with your health team, and a proactive approach to side‑effects are the three pillars that keep you on track.

There are 18 Comments

Stephanie Bryant

Took Sustiva for 2 years 🙌 My dreams were wild like a Netflix thriller but they faded after 3 weeks. Pro tip: sleep in total darkness and no caffeine after 4pm. Also, hydration is your BFF.

Still on it, viral load undetectable, and I’m hiking mountains now. 💪
Kaitlin Crockett

This is the most accurate summary I’ve seen. Clear, no fluff, just facts. Thank you.
Khanyisa Mhlongo

Oh my god I remember when I started this med-nightmares so vivid I swore I was in a Mandela documentary 😅 But after 10 days? Gone. Like magic. Now I sleep like a baby and my CD4 is through the roof. You got this, fam!
Leo Lee

People whine about dreams like it’s a tragedy. You’re alive because of this pill. Stop being dramatic. Take it at night, deal with it, and get on with your life. This isn’t a spa retreat.
Daniel Rogers

Sustiva changed my life. I was scared to start but now I’m running marathons and teaching yoga. The side effects? Real. Temporary. Worth it. You’re not broken-you’re healing. 💛
Drashti patel

Sometimes I think about how medicine is just a bridge between fear and freedom. Sustiva? It’s not a cure, but it’s the quiet hero that lets you breathe again. The dreams? Maybe your soul is just catching up. 🌙
Isabel Piaggi

i took sustiva for 18 months and the dizziness was insane at first like walking on a boat but after a week it was fine i stopped checking my phone before bed and my dreams got way less scary like i was watching a documentary not a horror movie
Tom McInnes

A well-structured and clinically sound overview. Appreciate the emphasis on adherence and monitoring.
Michael Tribone

Hey everyone-just wanted to say if you’re nervous about starting this, you’re not alone. I cried the first night I took it. But now? I’m living. I’m working. I’m dating. This med gave me back my future. You got this. We got this.
Nancy Lowry

If you can’t handle vivid dreams, maybe you shouldn’t be on antiretrovirals. This isn’t a choice-it’s survival. Stop treating it like a luxury. People in Africa take this with no sleep aids and no complaints.
Stephanie Cepero

I just wanted to say thank you to everyone who shared their stories. I’ve been terrified to start Sustiva, but reading this… I feel less alone. I’m starting next week. Praying I get through the first week okay 🤲
Manvika Gupta

i took sustiva for 6 months and the rash came after 10 days but my doctor told me to keep going and it faded like magic. dont panic if your skin itches. its normal. drink water. rest. youll be fine
Chloe McDonald

I started this last month. Day 1: felt like I was drunk. Day 7: still dizzy but sleeping better. Day 14: no dreams anymore. Honestly? It’s not that bad. Just give it time.
Hobert Finn Bodfish

You people are overreacting. I’ve been on this since 2010. Dreams? Yeah. Mood swings? Once. But my viral load is zero and I’m 45 and still lifting weights. Stop whining and take the pill.
Andrea Galetto

The fact that you’re even asking about side effects suggests you’re not ready for real treatment. This isn’t a lifestyle choice-it’s medical necessity. If you can’t handle it, don’t start.
Chris Remo

Man I was scared too. Took it at 10pm, woke up at 3am thinking I was in a spaceship. But I kept going. Now I don’t even remember the dreams. It’s like your brain just… resets. Trust the process.
Michael Herr

I’ve been on this for 8 years. No side effects after month one. My advice? Stick with it. Your future self will thank you.
Tracy Blake

I think about Sustiva not as a drug but as a silent guardian. It doesn’t shout. It doesn’t demand praise. It just sits in your medicine cabinet, waiting to do its quiet work while you dream of dragons and distant galaxies. And when you wake up, you’re still here. That’s the miracle. Not the absence of fear. The persistence through it. We are not broken. We are becoming. And this pill? It’s just the quiet architect of that becoming. Sometimes I thank it before I swallow. Not because I’m weird. Because I’m alive.