Dangers of Mixing Birth Control with Other Medicines

Have you ever heard of someone getting pregnant while on birth control? Maybe you even have a close friend or acquaintance who went through this situation, right? Well know that this type of case is more common than you think? and may be caused by mixing the birth control pill with other medications for various medical treatments.

In addition, there is the obvious health risk when using multiple medications simultaneously. According to a survey of the National Toxic Pharmacological Information System (Sinitox), Instituto Fio Cruz, indiscriminate use of medicines is responsible for most poisonings, even in front of the ingestion of poisons, pesticides and even drugs.

What happens is that most of the medicines we take are first processed in the liver. Then the active substances and ingredients are distributed throughout the body through the bloodstream.


In this passage through the liver, some substances require a greater effort from the organ so that they can be absorbed and that is why other substances from other medicines are not properly absorbed. That is why it is common to say that a medicine has? from the other.

In some cases, the birth control pill may lose up to 50% of its effect when mixed with other medicines. Of course, not all prescription drugs change the way contraceptive works, but there are about 400 drugs whose active ingredient somehow influences not only the effectiveness of the contraceptive. Some medicines can cause other problems when taken with contraceptives.

Contraceptive and remedies for general psychiatric treatment

Barbiturate medications such as phenobarbital (present in Gardenal) and carbamazepine (used in epilepsy pills) can dramatically reduce the effects of birth control.


Contraceptive and St. John's Wort

St. John's wort is a herbal medicine used as a natural antidepressant. What seems harmless can actually nullify the contraceptive effect by up to 60%.

Contraceptive and prokinetics / laxatives

Prokinetics are the medications used to treat reflux. Both prokinetics and laxatives decrease contraceptive residence time in the intestine, decreasing its absorption and, of course, its effectiveness.

Contraceptive and antibiotics

Most antibiotics interfere with the functioning of contraceptives, but those considered most harmful are those whose formula contains rifampicin. These cut the effect up to 50%.


Other combinations

Combining birth control and anti-inflammatories, antifungals, pain killers and even antimycotics can reduce the effectiveness of treatment. Anti-inflammatories, when taken in conjunction with contraceptives, can cause bleeding.

Indirect Factors

In addition to medications, other factors may also indirectly decrease the effect of contraception.

Drinking alcohol, for example, does not compromise treatment, as long as the woman does not overdo it, vomiting. Vomiting caused by excess alcohol, yes, can affect the effect of the pill. Similarly, eventual diarrhea may also be responsible for this decrease.

Cigarette smoking is another deciding factor. The combination between it and the pill increases the risk of cardiovascular disease, as the contraceptive method is made up of estrogen and progesterone. Thus, the only pill indicated for female smokers is that containing only progesterone in its composition.

It is crucial to talk to the doctor before mixing any medications. He can guide you properly so that you take proper care if the medication you are taking cannot be replaced.

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