Qlaira Drug Interactions

Effects of other medicinal products on Estradiol valerate + Dienogest (Qlaira): Interactions can occur with drugs that induce microsomal enzymes which can result in increased clearance of sex hormones and which may lead to breakthrough bleeding and/or contraceptive failure.
Women on treatment with with any of these drugs should temporarily use a barrier method in addition to the COC or choose another method of contraception. The barrier method should be used during the time of concomitant drug administration and for 28 days after their discontinuation.
Substances increasing the clearance of COCs (diminished efficacy of COCs by enzyme induction), e.g.: Phenytoin, barbiturates, primidone, carbamazepine, rifampicin, and possibly also oxcarbazepine, topiramate, felbamate, griseofulvin and products containing St. John's wort).
The effect of the CYP 3A4 inducer rifampicin was studied in healthy postmenopausal women. Co-administration of rifampicin with estradiol valerate/dienogest tablets led to significant decreases in steady state concentrations and systemic exposures of dienogest and estradiol. The systemic exposure of dienogest and estradiol at steady state, measured by AUC (0-24h), were decreased by 83% and 44%, respectively.
Substances with variable effects on the clearance of COCs, e.g.: When co-administered with COCs, many HIV/HCV protease inhibitors and non-nucleoside reverse transcriptase inhibitors can increase or decrease plasma concentrations of estrogen or progestin. These changes may be clinically relevant in some cases.
Substances decreasing the clearance of COCs (enzyme inhibitors): Dienogest is a substrate of cytochrome P450 (CYP) 3A4.
Strong and moderate CYP3A4 inhibitors such as azole antifungals (e.g. itraconazole, voriconazole, fluconazole), verapamil, macrolides (e.g. clarithromycin, erythromycin), diltiazem and grapefruit juice can increase plasma concentrations of the estrogen or the progestin or both.
In a study investigating the effect of CYP3A4 inhibitors (ketoconazole, erythromycin), steady state dienogest and estradiol plasma levels were increased. Co-administration with the strong inhibitor ketoconazole resulted in a 2.86-fold increase of AUC (0-24h) at steady state for dienogest and a 1.57-fold increase for estradiol. When co-administered with the moderate inhibitor erythromycin, the AUC (0-24h) of dienogest and estradiol at steady state were increased by 1.62-fold and 1.33-fold, respectively.
Effects of Estradiol valerate + Dienogest (Qlaira) on other medicinal products: Oral contraceptives may affect the metabolism of certain other drugs. Accordingly, plasma and tissue concentrations may either increase or decrease (e.g. lamotrigine). However, based on the in vitro data, inhibition of CYP enzymes by Estradiol valerate + Dienogest (Qlaira) is unlikely at the therapeutic dose.
Other forms of interactions: Laboratory tests: The use of contraceptive steroids may influence the results of certain laboratory tests, including biochemical parameters of liver, thyroid, adrenal and renal function, plasma levels of (carrier) proteins, e.g. corticosteroid binding globulin and lipid/lipoprotein fractions, parameters of carbohydrate metabolism and parameters of coagulation and fibrinolysis. Changes generally remain within the normal laboratory range.
Note: The prescribing information of concomitant medications should be consulted to identify potential interactions.