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Risky combinations

some meidcation next to a line of drugs

There are many possible interactions between recreational drugs and your HIV medication.

The following booster drugs are most likely to be involved in dangerous interactions with recreational drugs, recent research has shown:

  • ritonavir (Norvir) and
  • cobicistat (Tybost).

You’ll be taking one of those if you’re taking a protease inhibitor, such as:

if you’ve been prescribed the combination drug Kaletra, which contains the booster ritonavir.

What you need to know about HIV drug interactions:

Because cobicistat and ritonavir boost the power of protease inhibitors, they can also boost recreational drugs to a dangerous extent. The booster drug works by causing the liver to process the antiretroviral more slowly, causing its levels to be higher.

Your body processes some recreational drugs in the same way as it processes protease inhibitors, so they can also be boosted by cobicistat and ritonavir.

Drugs with a high risk of interacting with cobicistat and ritonavir:

  • ketamine
  • erectile dysfunction drugs eg, Viagra
  • benzodiazepines.

Drugs with a moderate risk of interacting with cobicistat and ritonavir:

  • crystal meth
  • mephedrone
  • MDMA (ecstasy).

Any risk is still serious – there have been deaths due to interactions between MDMA and ritonavir and crystal meth and ritonavir.

We don’t yet fully understand the different possible interactions, and advice changes over time as new evidence becomes available – that’s why it’s important to be upfront with your doctor or nurse about your drug use.

If you’ve just started taking treatment:

The risk of an interaction could be higher when you’ve just started to take HIV medication.

In these first weeks and months your body is getting used to processing antiretrovirals, so adding a recreational drug at this time could have added risks.

Be upfront with your doctor

This information is by no means exhaustive – it’s an introduction to the most common interactions we currently know about. If you’re using recreational drugs, tell your HIV doctor about it – they’ll explain any risks to you in more detail.

Don’t be nervous about bringing up the subject – your doctor will be used to talking about recreational drug use with patients, and would much rather know about it in case it affects your HIV treatment.

Can antiretrovirals lower the levels of recreational drugs in the blood?

Some non-nucleoside reverse transcriptase inhibitors (NNRTIs) can interact with some recreational drugs, making the levels lower because the liver processes them faster. This can be problematic if you take more of the recreational drug than you normally would, inject it or mix it with other drugs to try to get an effect.

The NNRTIs that can cause the interaction are:

The interaction affects the levels of:

  • cocaine
  • ketamine
  • erectile dysfunction drugs such as Viagra.

These antiretrovirals are NOT thought to pose a risk of interactions with recreational drugs:

  • the nucleoside reverse transcriptase inhibitor (NRTI) class
  • the non-nucleoside reverse transcriptase inhibitor (NNRTI) rilpivirine (Edurant)
  • the integrase inhibitors raltegravir (Isentress) and doluetegravir (Tivicay)
  • the CCR5 inhibitor maraviroc (Celsentri).

More information about interactions with common recreational drugs:

A lot of the information on this page has come from www.aidsmap.com

Anabolic steroids

Steroids and protease inhibitors can both raise levels of LDL (bad) cholesterol in the body. If you take anabolic steroids and are also taking a protease inhibitor, you need to be monitored closely, particularly if you have any risk factors for heart disease.


Poppers can interact with erectile dysfunction drugs such as Viagra, which can lead to a dangerous drop in blood pressure. Ritonavir and cobicistat can make this more likely.


NNRTIs including Efavirenz and nevirapine (Viramune) can reduce the levels of methadone in your body, resulting in the need for an increased dose. This needs to be monitored carefully to prevent you experiencing withdrawal symptoms.

The same can happen to a lesser degree with protease inhibitors and you may need an increased dose of methadone. Indinavir (Crixivan) has a lower chance of withdrawal symptoms.

Ritonavir reduces the blood levels of methadone and heroin so ritonavir-boosted protease inhibitors will have varying effects on methadone levels. Because of this, blood needs to be monitored.


There are no significant interactions between alcohol and HIV drugs. If drinking makes you vomit within an hour of taking HIV medication, take the dose again. However alcohol has been found to be more harmful if you’re living with HIV.

In addition, recent changes to Government guidelines recommend that both men and women should drink no more than 14 units each week.

If you take any other medication, however, check whether it’s safe to drink alcohol.

Cocaine and crack, LSD (acid), ketamine

No known dangerous interactions with anti-HIV drugs.


According to the University of Liverpool HIV Drug Interactions site there are potential but unstudied interactions between the active substance of cannabis and the NNRTIs delavirdine (Rescriptor), efavirenz (Sustiva) and etravirine (Intelence), as well as with atazanavir (Reyataz).


We don’t yet know much about the risk of interactions between either of these drugs and antiretrovirals.

There was a case in 1999 where someone taking ritonavir and saquinavir nearly overdosed on GHB, raising concerns that protease inhibitors may increase levels of GHB. However there have been no further studies.

University of Liverpool’s Drug Interactions site advises that there are potential interactions between GHB and the protease inhibitor class of drugs as well as the booster drugs ritonavir and cobicistat, the NNRTI delavirdine (Rescriptor), the integrase inhibitor elvitegravir (Vitekta) and the combination drug E/C/F/TAF (elvitegravir (Vitekta), cobicistat (Tybost), emtricitabine (Emtriva) and tenofovir alafenamide fumarate.

However because of a lack of research most people conclude that the risk of interactions concerning GHB and GBL is relatively unknown.

See this drug interaction chart from University of Liverpool for more information.

More about drug use:



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The Information Standard: Certified member

This article was last reviewed on 25/5/2016 by Anna Peters

Date due for the next review: 25/5/2019

Content Author: Kerri Virani

Current Owner: Health Promotion

More information:

Interactions between HIV treatment and recreational drugs, Roger Pebody, NAM aidsmap, November 2015

HIV treatment ‘booster drugs’ are most likely to have dangerous interactions with methamphetamine, mephedrone, MDMA and ketamine - Interactions also possible between erectile dysfunction drugs and benzodiazepines, Roger Pebody, NAM aidsmap, August 2015

Interactions with recreational drugs, NAM aidsmap

Alcohol guidelines review – report from the guidelines development group to the UK Chief Medical Officers, Department of Health, January 2016

New alcohol guidelines show increased risk of cancer, Department of Health (gov.uk), January 2016

UK Chief Medical Officers’ Alcohol Guidelines Review, Summary of the proposed new guidelines, Department of Health, January 2016

New Government alcohol unit guidelines, Drinkaware, February 2016

Alcohol units, NHS Choices, April 2015

Moderate alcohol consumption may be more harmful to people with HIV, Keith Alcorn, NAM aidsmap, February 2016

Cocaine, NAM aidsmap

Cannabis, NAM aidsmap

Gamma-hydroxybutytae, NAM aidsmap

HIV drug interactions - Delavirdine/cannabis, University of Liverpool, May 2016

HIV drug interactions - Atazanavir/cannabis, University of Liverpool, May 2016

HIV drug interactions - Efavirenz/cannabis, University of Liverpool, May 2016

HIV drug interactions - Etravirine/cannabis, University of Liverpool, May 2016

HIV drug interactions - Elvitegravir/Cobi/FTC/TDF/ Gamma-hydroxybutyrate, University of Liverpool, May 2016

HIV drug interactions - Atazanavir/ Gamma-hydroxybutyrate, University of Liverpool, May 2016

HIV drug interactions - Cobicistat (with ATV or DRV)/Gamma-hydroxybutyrate, University of Liverpool, May 2016

HIV drug interactions - Darunavir/Gamma-hydroxybutyrate, University of Liverpool, May 2016

HIV drug interactions - Delavirdine/Gamma-hydroxybutyrate, University of Liverpool, May 2016

HIV drug interactions - E/C/F/TAF/Gamma-hydroxybutyrate, University of Liverpool, May 2016

AIDS InfoNet (2009) Recreational Drugs and HIV:

Methadone and HIV Medications: Drug Interactions, Seattle Treatment Education Project & The Body (2003)  

Viagra (sildenafil), NAM, Aidsmap

Anabolic Steroids, NAM, Aidsmap (2011)

Viagra, Poppers & Crystal: To Mix or Nor to Mix, Project Neon, April 2001

Interactions with recreational drugs, NAM, Aidsmap (2012)

Drug Interactions, Drugscope (2011)

Alcohol, NAM, Aidsmap, Michael Carter (2011)

Methadone hydrochloride (Methadose), NAM, Aidsmap (2012)