It is a commonly used anti-tuberculosis drug, which can accelerate the metabolism of norethisterone and ethinylestradiol, the main components of oral contraceptives, reduce the concentration of drugs in blood, and may also cause partial shedding of endometrium to cause intravenous drip hemorrhage or inexhaustible leaching. At the same time, it can reduce the contraceptive effect and lead to contraceptive failure.
Some people have observed 38 women who took contraceptives while using ampicillin, neomycin, tetracycline, compound sulfamethoxazole and chloramphenicol, resulting in contraceptive failure. It was found that the reason for its failure was that antibiotics inhibited intestinal bacteria and greatly reduced the amount of glucuronidase produced by antibiotics, thus affecting the absorption of contraceptives in intestinal tract and reducing the concentration of contraceptives in blood, thus failing to achieve contraceptive effect.
III. Antiepileptic Drugs
These drugs are enzyme inducers, Such as phenobarbital, phenytoin, carbamazepine, parepileptin, etc. When women suffering from epilepsy take such drugs, they can promote the increase of drug metabolizing enzymes in hepatocytes, accelerate the destruction of oral contraceptive efficacy, and at the same time also increase the binding rate of progesterone and globulin, greatly reduce the concentration of free progesterone, leading to the failure of contraception.
This is an antifungal drug. When it is used together with contraceptives, it can change the activity of liver granulase, reduce the concentration of steroid hormones and reduce menstrual blood, resulting in contraceptive failure. It has been reported abroad that more than 20 women taking contraceptives have reduced menstrual blood volume in 15, amenorrhea in 5 and pregnancy in 2 after taking griseofulvin.
5. Enzyme promoter
For example, sedative sleeping pills such as Mianertong and other drugs for rheumatoid arthritis such as Baotaisong. These drugs have enzymatic effect, which can promote the metabolic activity of liver granule enzyme catalyzed drugs, accelerate the metabolism of oral contraceptives and reduce the contraceptive effect. If sleeping pills must be used, diazepam can be selected instead of other sedative sleeping pills.
Six, antihypertensive drugs
Oral contraceptives containing estrogen can enhance the secretion of lactogen stimulated by antihypertensive drugs such as reserpine and methyldopa, which can cause hyperplasia of mammary glands and lactation. In addition, antipsychotic drugs such as chlorpromazine and imipramine can also have similar effects. Therefore, women taking contraceptives should avoid using these drugs.
Anticoagulants (such as bicoumarins) can inhibit the synthesis of prothrombin and coagulation factors in the body, while contraceptives can increase them, thus reducing the effect of bicoumarins, so contraceptives should not be taken during treatment.
Contraceptive pills can promote the deterioration of diabetes, increase the patient’s insulin demand (8-20 units per day), and may increase the incidence of cardiovascular diseases in diabetic patients. Therefore, drug contraception is not suitable for diabetic patients.
IX. Corticosteroid Drugs
Oral contraceptives can increase the efficacy of corticosteroids (such as prednisone, dexamethasone, etc.), delay their metabolism, and enhance their effects and side effects. Therefore, when both are taken at the same time, the dosage of corticosteroids must be reduced.