Date of report 17 Mar 2026
Reported case interaction between
Raltegravir and Carbamazepine
Raltegravir and Carbamazepine
Drugs suspected to be involved in the DDI
Complete list of drugs taken by the patient
Carbamazepine 200mg mane 400mg PM; Solifenacin 5mg OD; Tamsulosin 400mcg OD; Amlodipine 10mg OD; Lisinopril 5mg OD; Propranolol 80mg m/r OD; Sertraline 50mg OD; Omeprazole 20mg OD PRN; Vit D OTC
Clinical case description
A patient receiving carbamazepine for epilepsy had been concomitantly treated with raltegravir 1200 mg QD for several years. This combination was only identified during a routine HIV follow-up visit, after approximately 6 years of coadministration. Despite the potential for drug–drug interactions, the patient had consistently maintained virological suppression and reported good adherence to all medications.
Clinical Outcome
Editorial Comment
Coadministration of carbamazepine and raltegravir has not been formally studied but may decrease raltegravir concentrations, as raltegravir is primarily metabolized by UGT1A1 and in vitro data suggest that carbamazepine induces this enzyme. Coadministration with once-daily raltegravir (1200 mg once daily) is not recommended, as strong enzyme inducers are expected to have a more pronounced effect on raltegravir Cmin when administered once daily.
This is an interesting case. However, it is unfortunate that no information on raltegravir trough concentrations or UGT1A1 genotype is available. For instance, if the patient were a reduced UGT1A1 metabolizer (e.g., Gilbert’s syndrome), the impact of enzyme induction by carbamazepine might be attenuated.
If carbamazepine or another strong UGT1A1 inducer is required in combination with an integrase strand transfer inhibitor (INSTI), dolutegravir 50 mg twice daily is the preferred option.
University of Liverpool Recommendation
Potential interaction - may require close monitoring, alteration of drug dosage or timing of administration
Personal information from the specialist
Other authors