Once-daily (600mg)          Twice-daily (400 mg)


  • Raltegravir (tradename Isentress HD or Isentress) is an integrase inhibitor.

There are now two versions, both of which give the same active amount of drug.

  1. New once-daily formulation: 2 x 600 mg tablets. (Isentress HD).
  2.  Original twice-daily formulation: 1 x 400mg tablet, twice daily. (Isentress)
  • Raltegravir can be taken with or without food.
  • Side effects: diarrhoea, nausea, rash and headache. May cause depression (rare). Raltegravir is one of the few HIV meds that does not worsen cholesterol or triglyceride levels.
  • Drug interactions: raltegravir also has relatively few drug interactions but should not be taken with multivitamin supplement that contain calcium, magnesium or aluminium. Separating the raltegravir and multivitamin dose by at least six hours minimises the interaction.
  • This is only for supplements – it is NOT a concern for foods like milk and cheese that contain calcium.
  • Other notes: raltegravir can be used in combination with other drugs that are active to work against nuke, NNRTI and PI-resistant HIV.
  • Raltegravir is included as a recommended option for first-line treatment in both UK and US treatment guidelines.

Further information

The European patient leaflet and detailed Product Information for raltegravir are available at this link at the European Medicines Agency (EMA) website.

The Patient Information is a simplified summary: what the drug is, why it is used, results from studies and cautions including side effects.

The Product Information is a detailed technical summary that you can access as a PDF file by clicking the ‘Product Information’ tab. It describes more precisely how the drug works and how it is processed by your body. This includes, for example, reported food interaction studies in terms of calories or fat content. It includes more details of the study results and a full list of side effects and drug interactions.(Direct link to PDF).

This post was updated in January 2022.