Known interactions and possible interactions with medicines

Combinations that are not mentioned in this summary should not be understood to be safe.


  • Kaletra and Norvir strengthen the effect of XTC, making an overdose more likely.
  • If you take protease inhibitors, it is even more important to drink plenty of water when you take XTC.


  • Protease inhibitors can strengthen the effect of LSD, making an overdose more likely.


  • Combining poppers and erection pills can be dangerous.
  • There are no known interactions with HIV medicines.


  • A risk in connection with two kinds of HIV medicines (protease inhibitors and non-nucleosides) cannot be excluded.


  • Benzos that you can buy on the street may combine poorly with HIV medicines.
  • Valium may not be used together with Norvir.
  • Stilnoct may not be used together with protease inhibitors.
  • Halcion and Dormicum may not be used together with protease inhibitors or with Atripla or Stocrin.


  • Phenobarbital (Luminal) decreases the effect of protease inhibitors and Viramune. Protease inhibitors will actually increase the strength of phenobarbital, making an overdose more likely.


  • With GHB, the dosage is critical. A combination with Kaletra or Norvir will strengthen the effect of GHB, making an overdose more likely.
  • It is better not to combine GHB with any other substance: not with party drugs, alcohol or tranquillizers, but also not with any (over-the-counter) medications for insomnia or allergies.

Heroine and morphine

  • Kaletra and Norvir, but probably also other HIV medicines in the categories of protease inhibitors and non-nucleosides, will decrease the effect of heroine and morphine.


  • Protease inhibitors, Atripla and Stocrin can all strengthen the effect of ketamine, making an overdose more likely.
  • Watch out for the combination of ketamine with alcohol, since you can become seriously exhausted from that.


  • Atripla, Kaletra, Norvir, Stocrin, Telzir, Viracept and Viramune will all decrease the effect of methadone. The effect can be reduced so much that some people will get withdrawal symptoms.

You can find more extensive overviews in Dutch on:





Hiv Vereniging Nederland

Eerste Helmersstraat 17


020 6 160 160
>> directions



020 689 25 77

For questions about living with HIV. Available monday, tuesday and thursday from 2 PM till 10 PM

>> read more


Support the association and become a member
>> contact Servicepunt