https://interactions.guidetherapeutiquevih.com/en/interaction-details?id=8194
No pharmaceutical opinion available for this interaction.
Darunavir / ritonavir can inhibit the metabolism (CYP 3A4) and increase the plasma concentration of Carbamazepine.
Carbamazepine can induce the metabolism (CYP 3A4) and decrease the plasma concentration of Darunavir / ritonavir.
Probably without any clinical consequence.
See comments.
No dosage adjustment recommended.
Monitor for clinical efficacy.
–
Possible increase of adverse effects.
No a priori dosage adjustment is recommended.
Monitor for adverse effects.
Monitor drug levels and adjust the dose if necessary.
A decrease in dosage of 25 to 50% may be necessary.
See comments for further details.
As clinically indicated : brivaracetam, gabapentin, lacosamide, lamotrigine, levetiracetam, pregabalin, rufinamide, topiramate, vigabatrin, zonisamide.
Carbamazepine adverse effects : disorientation, ataxia, lethargy, drowsiness, nausea, vomiting, headache, diplopia, dizziness, leukopenia and hyponatremia.
Carbamazepine
Darunavir plasma level
CD4+
Viral load HIV
Reference number |
---|
# patients |
HIV |
Dose |
Frequency |
AUC |
Cmax |
Cmin |
2241 |
---|
16 |
- |
200 mg |
BID |
+ 45% |
+ 43% |
+ 54% |
2241 |
---|
16 |
- |
600/100 mg |
BID |
- 1% |
+ 4% |
- 15% |
Ref #2241: The active metabolite of carbamazepine has decreased: AUC and Cmax by 54% and Cmin by 52% .
The author concluded that carbamazepine may need to be reduced by 25-50% but no dose adjustment for DRV/r is recommended.
Ref #3570: TDM data were evaluated 11 HIV-positive patients treated concomitantly with carbamazepine or oxcarbazepine and antiretrovirals for at least 3 months. All the TDM evaluations for carbamazepine and oxcarbazepine were within therapeutic ranges. TDM results of darunavir measured in these patients were comparable to those in the control group.
Ref #1304 : Reported case of a 20-year-old patient who developed vomiting, dizziness, elevated liver enzymes, and increased carbamazepine concentration by 87% following the addition of one dose of ritonavir 200 mg. Symptoms started within 12 hours after the first dose of ritonavir. In order to obtain a concentration within the therapeutic index, the dose of carbamazepine was reduced from 750 to 280 mg QD. Several other cases of acute toxicity to carbamazepine 2 to 4 days after the addition of ritonavir have been reported. See ritonavir + carbamazepine.
Ref #2090: Another case reported of a 50 year man who developed excessive drowsiness following the introduction of lopinavir/ritonavir and it was found that his serum carbamazepine concentration had increased by 46%. His antiretroviral therapy was then changed to nelfinavir 1250 mg BID but 3 days later the same symptoms appeared with 53% increase in carbamazepine. The symptoms of carbamazepine toxicity disappeared after a carbamazepine dose reduction of 33%. See lopinavir/ritonavir + carbamazepine.