The use of anabolic steroids such as Winstrol may be associated with serious adverse reactions, many of which are dose related. Patients should be placed on the lowest possible effective dose. Medications that may interact with Winstrol include anticoagulants (blood thinners), insulin , or an oral diabetes medicine. Tell your doctor all medications you are taking. Winstrol is known to cause birth defects in a fetus. Do not take this medication if you are pregnant or could become pregnant during treatment. It is not known whether Winstrol is excreted in human milk. Many drugs are excreted in human milk and there is the potential for adverse reactions in nursing infants from anabolic steroids. Consult your doctor before breastfeeding.
A few other drugs may also affect birth control reliability. The antifungal medicine griseofulvin may lead to lower levels of birth control hormones and reduce the effectiveness of birth control pills. Certain seizures drugs, for example the anticonvulsant medications such as carbamazepine (Tegretol) , phenytoin (Dilantin) , primidone (Mysoline) , and phenobarbital can also lower the effectiveness of combined birth control pills. Some HIV medications may also affect birth control effectiveness. Two small studies suggest that St. John's wort can induce liver enzymes, which may increase birth control pill metabolism and reduce therapeutic efficacy.
CHCs containing EE may inhibit the metabolism of other compounds (., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole) and increase their plasma concentrations. CHCs have been shown to decrease plasma concentrations of acetaminophen, clofibric acid, morphine, salicylic acid, and temazepam. Significant decrease in plasma concentration of lamotrigine has been shown, likely due to induction of lamotrigine glucuronidation. This may reduce seizure control; therefore, dosage adjustments of lamotrigine may be necessary.