Buying medicine onlineSome websites that sell medicine can be not state-licensed pharmacies or aren't pharmacies at all; or may give a diagnosis that is not correct and sell medicine that is not right for you or your condition; or won't protect your personal information. Be sure your privacy is protected: look for privacy and security policies that are easy-to-find and easy-to-understand. Don't give any personal information such as social security number, credit card, or medical or health history, unless you are sure the website will keep your information safe and private. Make sure the site requires a prescription and has a pharmacist available for questions.
Precautions for over-the-counter medicineThere are more opportunities today than ever before to learn about your health and to take better care of yourself. It is also more important than ever to know about the medicines you take. Drug interactions may make your drug less effective, cause unexpected side effects, or increase the action of a particular drug. Some drug interactions can even be harmful to you. Early in a drug's development, companies conduct research to detect or predict potential interactions between drugs. Experts evaluate the drug-interaction studies as part of assessing a drug's safety. The most important enzymes in the liver that metabolize drugs are called the cytochrome P450 family of enzymes. These enzymes break down drugs when they pass through the liver or small intestine. Over the last several years, there has been a substantial increase in the number of drug-interaction studies the FDA sees in new drug applications. If drug interactions are significant enough, they can prevent a drug from being approved by the FDA. If the agency determines that known drug interactions can be managed and that a drug's benefits outweigh the risks for the intended population, a drug will be approved. Drug-interaction information then goes into the drug's labeling in the sections on "clinical pharmacology," "precautions," "warnings," "contraindications," and "dosage and administration." So rather than asking patients what medications they take, doctors should make the questions specific: "Are you taking any over-the-counter medication? Are you taking any herbal treatments or vitamins?" Some antibiotics, such as rifampin, can lower the effectiveness of birth control pills. Sildenafil, the active ingredient in the erectile dysfunction drug Viagra, should not be taken with nitrates for heart treatment because of the potential for dangerously low blood pressure. Drug interactions with dietary supplements includes herbs and vitamins, which can interact with drug-metabolizing enzymes. St. John's wort is an herb commonly used by people with cancer to improve mood, but research has shown it interferes with the metabolism of irinotecan, a standard chemotherapy treatment. Vitamin K (in dietary supplements or food) produces blood-clotting substances that may reduce the effectiveness of blood-thinning medicines like warfarin. Drug interactions with food and beverages, for example, taking quinolone antibiotics such as ciprofloxacin with food and drinks such as colas, coffee, and chocolate that contain caffeine may cause excitability and nervousness. There can be a potentially fatal increase in blood pressure if food containing tyramine is eaten when taking monoamine oxidase inhibitors, drugs that treat mood disorders. Examples of food with tyramine are cheese and soy sauce. Grapefruit juice should not be taken with certain blood pressure-lowering drugs or cyclosporine for the prevention of organ transplant rejection. Alcohol should not be taken with pain relievers such as Tylenol (acetaminophen) or ibuprofen because of the increased risk of liver damage or stomach bleeding.
|
