Simultaneous coadministration of calcium carbonate (1200 mg) and dolutegravir (50 mg single dose) to fasting subjects decreased dolutegravir Cmax, AUC and Cmin by 37%, 39% and 39%, respectively. Simultaneous coadministration to fed subjects increased dolutegravir Cmax, AUC and Cmin by 7%, 9% and 8%, respectively. Coadministration of calcium carbonate 2 h after dolutegravir had no effect on dolutegravir Cmax and decreased dolutegravir AUC and Cmin by 6% and 10%, respectively. Dolutegravir should be administered 2 hours before or 6 hours after taking medications containing polyvalent cations, such as calcium supplements. The US Prescribing information suggests that, alternatively, dolutegravir and calcium supplements can be taken together with food. Medicinal products that reduce dolutegravir exposure (e.g. calcium supplements) should be avoided in the presence of integrase class resistance.

Coadministration has not been studied but based on metabolism and clearance a clinically significant interaction is unlikely. Paracetamol is mainly metabolized by glucuronidation (via UGT1A9 (major), UGT1A6, UGT1A1, UGT2B15) and sulfation and, to a lesser extent, by oxidation. Dolutegravir is not expected to inhibit or induce CYP450 or UGT enzymes at clinically relevant concentrations.

Coadministration has not been studied but based on metabolism and clearance a clinically significant interaction is unlikely. Aspirin is rapidly deacetylated to form salicylic acid which is further glucuronidated by several UGTs (major UGT1A6). In addition, coadministration with an NSAID is unlikely to be of concern for nephrotoxicity as tenofovir alafenamide results in 90% lower systemic levels of tenofovir compared to tenofovir-DF. Dose Descovy according to the concomitant antiretroviral.

Coadministration has not been studied but based on metabolism and clearance a pharmacokinetic interaction is unlikely. Paracetamol is mainly metabolized by glucuronidation (via UGT1A9 (major), UGT1A6, UGT1A1, UGT2B15) and sulfation and, to a lesser extent, by oxidation. Emtricitabine and tenofovir alafenamide do not interact with this metabolic pathway. Dose Descovy according to the concomitant antiretroviral.

Coadministration has not been studied but a clinically significant pharmacokinetic interaction is unlikely. Calcium is eliminated through faeces, urine and sweat. Dose Descovy according to the concomitant antiretroviral.

Coadministration of dolutegravir (50 mg once daily) with emtricitabine/tenofovir alafenamide (200/10 mg, once daily) increased tenofovir AUC and Cmax by 25% and 10% (n=10). No significant effects were observed on dolutegravir pharmacokinetics relative to historical controls. Coadministration of dolutegravir (50 mg once daily) and tenofovir alafenamide/emtricitabine/elvitegravir/cobicistat (10/200/150/150 mg) had no significant effect on the pharmacokinetics of dolutegravir and tenofovir alafenamide. The recommended dose of Descovy for HIV-1 treatment is 200/25 mg once daily.