Coadministration has not been studied. Nevirapine, an inducer of CYP3A4, could potentially decrease dolutegravir concentrations. The US Prescribing Information advises that coadministration should be avoided because there are insufficient data to make dosing recommendations. However, the European SPC recommends a dolutegravir dose of 50 mg twice daily with nevirapine, except in the presence of integrase class resistance when alternative combinations that do not include nevirapine should be considered.