Rigevidon Drug Interactions

Note: The prescribing information of concomitant medications should be consulted to identify potential interactions.
Pharmacodynamic interactions: Concomitant use with the medicinal products containing ombitasvir/paritaprevir/ritonavir and dasabuvir, with or without ribavirin may increase the risk of ALT elevations (see Contraindications and Precautions). Therefore, Rigevidon users must switch to an alternative method of contraception (e.g., progestagen-only contraception or non-hormonal methods) prior to starting therapy with this combination drug regimen. Rigevidon can be restarted 2 weeks following completion of treatment with this combination drug regimen.
Pharmacokinetic interactions: Effects of other medicinal products on Rigevidon tablets: 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.
Management: Enzyme induction can already be observed after a few days of treatment. Maximal enzyme induction is generally seen within a few weeks. After the cessation of drug therapy enzyme induction may be sustained for about 4 weeks.
Short-term treatment: Women on treatment with enzyme inducing drugs should temporarily use a barrier method or another method of contraception in addition to the COC. The barrier method must be used during the whole time of the concomitant drug therapy and for 28 days after its discontinuation.
If the drug therapy runs beyond the end of the tablets in the COC pack containing 21 tablets, the next COC pack should be started right after the previous one without the usual tablet-free interval.
Long-term treatment: In women on long-term treatment with enzyme-inducing active substances, another reliable, nonhormonal, method of contraception is recommended.
The following interactions have been reported in the literature: Substances increasing the clearance of COCs (diminished efficacy of COCs by enzyme-induction), e.g.: Barbiturates, bosentan, carbamazepine, phenytoin, primidone, rifampicin, and HIV medication ritonavir, nevirapine and efavirenz and possibly also felbamate, griseofulvin, oxcarbazepine, topiramate and products containing the herbal remedy St. John's Wort (Hypericum perforatum).
Substances with variable effects on the clearance of COCs: When co-administered with COCs, many combinations of HIV protease inhibitors and non-nucleoside reverse transcriptase inhibitors, including combinations with HCV inhibitors can increase or decrease plasma concentrations of estrogen or progestins. The net effect of these changes may be clinically relevant in some cases.
Therefore, the prescribing information of concomitant HIV/HCV medications should be consulted to identify potential interactions and any related recommendations. In case of any doubt, an additional barrier contraceptive method should be used by women on protease inhibitor or non-nucleoside reverse transcriptase inhibitor therapy.
Effects of Rigevidon tablets on other medicinal products: Oral contraceptives may affect the metabolism of certain other active substances. Accordingly, plasma and tissue concentrations may either increase (e.g. ciclosporin) or decrease (e.g. lamotrigine).
Other forms of interaction: Troleandomycin: Troleandomycin may increase the risk of intrahepatic cholestasis during coadministration with COCs.
Modafinil: Risk of reduction of contraceptive efficacy during the treatment and a cycle after discontinuation of the treatment with modafinil, because of its enzyme inducer potential.
Use normodosed oral contraceptives or another contraceptive method.
Vemurafenib: Risk of reduction of estrogen and progestogen concentrations, with a consequent risk of lack of efficacy.
Perampanel: For perampanel doses greater or equal to 12 mg/d: risk of reduced contraceptive efficacy.
Preferably use another contraceptive method, especially mechanical.
Rufinamide: Moderate reduction in ethinylestradiol concentrations. Preferably use another contraceptive method, especially mechanical.
Etoricoxib: Increased concentrations of ethinylestradiol with etoricoxib.
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 blood coagulation and fibrinolysis. The changes generally remain within the normal laboratory range.