References UK clinical guidance from the NHS, the British HIV Association (BHIVA), and the British Association for Sexual Health and HIV (BASHH). Last updated: April 2026.
HIV medications are processed through the liver and kidneys using many of the same pathways as other drugs. This means they can interact with prescription medicines, over-the-counter remedies, supplements and recreational drugs. Some interactions are minor, but others can be dangerous — either reducing the effectiveness of your HIV treatment or raising other drug levels to toxic concentrations.
Here’s what you need to know to stay safe.
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Why Interactions Happen
Most HIV drug interactions involve liver enzymes, particularly the CYP450 system. Some HIV drugs speed up these enzymes (inducers), breaking down other medicines faster. Others slow them down (inhibitors), causing other drugs to build up. Boosted protease inhibitors (with ritonavir or cobicistat) are the biggest culprits.
Common Interactions by Drug Class
| HIV Drug Class | Interaction Risk | Key Concerns |
|---|---|---|
| Boosted PIs (darunavir/r, atazanavir/r) | High | Statins, steroids, erectile dysfunction drugs, recreational drugs |
| NNRTIs (efavirenz, rilpivirine) | Moderate | Acid-reducing drugs (rilpivirine), rifampicin, contraceptives |
| INSTIs (dolutegravir, bictegravir) | Lower | Antacids, calcium, iron, magnesium supplements, metformin |
| NRTIs (tenofovir, emtricitabine, lamivudine) | Low | Nephrotoxic drugs with tenofovir |
Medicines That Commonly Interact
- Statins — simvastatin and lovastatin are contraindicated with boosted PIs. Use pravastatin or rosuvastatin instead
- Proton pump inhibitors (omeprazole, lansoprazole) — contraindicated with rilpivirine-containing drugs
- Inhaled corticosteroids (fluticasone) — can cause Cushing’s syndrome with ritonavir/cobicistat
- Erectile dysfunction drugs — doses must be reduced with boosted PIs
- Anticonvulsants — carbamazepine, phenytoin can reduce many HIV drug levels
- Rifampicin — interacts with almost all HIV drugs; rifabutin is usually preferred
- St John’s Wort — contraindicated with all HIV treatment
- Antacids, calcium, iron — take 2 hours before or 6 hours after INSTIs
Recreational Drugs
This is a serious safety concern. Boosted PIs dramatically raise levels of:
- MDMA/ecstasy — can reach life-threatening concentrations
- Methamphetamine — dangerously increased
- GHB/GBL — unpredictable interactions
- Ketamine — levels may be raised
If you use recreational drugs, be honest with your HIV team. They can help you understand risks and may adjust your regimen.
How to Stay Safe
- Tell your HIV team about every medicine, supplement and recreational drug you use
- Check interactions before starting anything new — your HIV pharmacist can help
- Use the Liverpool HIV Drug Interactions website (hiv-druginteractions.org) as a reference
- Never take St John’s Wort with HIV treatment
- Ask before buying over-the-counter medicines
Read more: Ritonavir | Biktarvy | What is HIV?
Frequently Asked Questions
Can I take paracetamol with HIV medication?
Yes. Paracetamol is generally safe with HIV treatment at standard doses. Avoid exceeding the recommended daily maximum.
Can I take ibuprofen?
Occasionally, yes. But regular use of NSAIDs can affect kidney function, which is particularly relevant if you’re on tenofovir. Check with your HIV team if you need regular pain relief.
Where can I check drug interactions?
The Liverpool HIV Drug Interactions website (hiv-druginteractions.org) is the standard reference used by UK clinicians. Your HIV pharmacist is also an excellent resource.
Related reading
- Injectable HIV Treatment: Everything You Need to Know
- Are HIV Tests Accurate If You're on PrEP, PEP or ART?
- CD4/CD8 Ratio: What It Means and Why It Matters
- CD4 Counts Explained: What Your Numbers Mean
- Changing HIV Treatment: When, Why and How
Sources
- NHS — Sexual health conditions
- BASHH — UK clinical guidelines for STI management
- British HIV Association (BHIVA) — HIV treatment guidelines
- Terrence Higgins Trust — sexual health information
- UK Health Security Agency — STI surveillance data
Steve Page is a recognised expert on Sexually Transmitted Diseases (STDs) and STD treatments, having published numerous articles in peer-reviewed journals and presented his research at conferences around the world. He has an in-depth understanding of the latest medical research on STDs, and is an advocate for the development of new treatments and protocols to improve the health of those affected. In addition to his research, he has dedicated his career to understanding the causes and symptoms of STDs, as well as how to best treat those impacted.
