Dronabinol

Inhibitors and Inducers of CYP2C9 and CYP3A4 : May alter dronabinol systemic exposure; monitor for dronabinol-related adverse reactions or loss of efficacy. ( 7.2 ) Highly Protein-Bound Drugs : Potential for displacement of other drugs from plasma proteins; monitor for adverse reactions to concomitant narrow therapeutic index drugs (e.g., warfarin, cyclosporine, or amphotericin B) when initiating or increasing the dosage of SYNDROS. ( 7.3 )

7.1 Disulfiram and Metronidazole SYNDROS contains 50% (w/w) dehydrated alcohol and 5.5% (w/w) propylene glycol, which can produce disulfiram-like reactions when co-administered with disulfiram or other drugs that produce this reaction (e.g., metronidazole). Discontinue products containing disulfiram or metronidazole at least 14 days before starting treatment with SYNDROS and do not administer these products within 7 days of completing treatment with SYNDROS [see Contraindications ( 4 ), Warnings and Precautions ( 5.3 )] .

When administered concomitantly with propylene glycol, ethanol competitively inhibits the metabolism of propylene glycol, which may lead to elevated concentrations of propylene glycol. However, the contribution of propylene glycol, if any, to the interaction between disulfiram and SYNDROS is unknown.

7.2 Effect of Other Drugs on Dronabinol Dronabinol is primarily metabolized by CYP2C9 and CYP3A4 enzymes. Inhibitors of these enzymes may increase, while inducers may decrease, the systemic exposure of dronabinol and/or its active metabolite resulting in an increase in dronabinol-related adverse reactions or loss of efficacy of SYNDROS. Monitor for increased dronabinol-related adverse reactions when SYNDROS is co-administered with inhibitors of CYP2C9 (e.g., amiodarone, fluconazole) and inhibitors of CYP3A4 enzymes (e.g., ketoconazole, itraconazole, clarithromycin, ritonavir, erythromycin, grapefruit juice).

7.3 Highly Protein-Bound Drugs Dronabinol is highly bound to plasma proteins, and therefore, might displace and increase the free fraction of other concomitantly administered protein-bound drugs. Although this displacement has not been confirmed in vivo, monitor patients for increased adverse reactions to narrow therapeutic index drugs (e.g., warfarin, cyclosporine, amphotericin B) when initiating treatment or increasing the dosage of SYNDROS.

8.1 Pregnancy Risk Summary SYNDROS, a synthetic cannabinoid containing alcohol, may cause fetal harm. Avoid use of SYNDROS in pregnant women. Although there is little published data on the use of synthetic cannabinoids during pregnancy, use of cannabis (e.g., marijuana) and use of alcohol during pregnancy have been associated with adverse fetal/neonatal outcomes (see Clinical Considerations ) . Cannabinoids have been found in the umbilical cord blood from pregnant women who smoke cannabis.

In animal reproduction studies, no teratogenicity was reported in mice administered dronabinol (delta-9-THC) at up to 30 times the MRHD (maximum recommended human doses) and up to 5 times the MRHD for patients with AIDS and cancer, respectively. Similar findings were reported in pregnant rats administered dronabinol at up to 5 to 20 times the MRHD and 3 times the MRHD for patients with AIDS and cancer, respectively. Decreased maternal weight gain and number of viable pups and increased fetal mortality and early resorptions were observed in both species at doses which induced maternal toxicity.

In rats, maternal administration of dronabinol from pregnancy (implantation) through weaning was associated with maternal toxicity, including mortality of pups, and adverse developmental and neurodevelopmental effects on the pups at 2 to 20 times the MRHD for patients with AIDS and less than and up to 3.3 times the MRHD for patients with cancer. (see Data ) . The estimated background risk of major birth defects and miscarriage for the indicated populations are unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S.

general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. Clinical Considerations Fetal/Neonatal Adverse Reactions Published studies suggest that during pregnancy, the use of cannabis, which includes THC, whether for recreational or medicinal purposes, may increase the risk of adverse fetal/neonatal outcomes including fetal growth restriction, low birth weight, preterm birth, small-for-gestational age, admission to the neonatal intensive care unit, and stillbirth. Therefore, use of cannabis during pregnancy should be avoided. SYNDROS contains alcohol.

Published studies have demonstrated that alcohol is associated with fetal harm including central nervous system abnormalities, behavioral disorders, and impaired intellectual development. Avoid use of SYNDROS in pregnant women. Data Human Data Delta-9-THC has…