Beware of possible drug interactions

Dec 12, 2011, 3:06 GMT

Berlin - Drugs can affect and even interfere with each another. People who take several drugs should therefore acquaint themselves with possible interactions. This also applies to over-the-counter medications such as painkillers or dietary supplements with calcium, which can alter the effects of other medications.

'Someone taking a medication for the first time, in particular, should inquire in the pharmacy about possible interactions,' advised Erika Fink, president of Germany's Federal Chamber of Pharmacists. Interferences are also listed in patient information leaflets.

An interference may increase or decrease a drug's effectiveness and cause side-effects. Antibiotics or over-the-counter antidepressants can hamper the effectiveness of contraceptive pills, for example, which could result in an unwanted pregnancy.

Over-the-counter stomach medications can delay the effects of other drugs by slowing their absorption into the blood. This can be avoided by taking the medications at different times.

Some drug combinations intensify each other's effects: Simultaneously taking an anticoagulant and a painkiller with acetylsalicylic acid (ASA) increases the risk of bleeding. Other drug combinations can be beneficial: There are antibiotics that complement each other and are always co-administered.

Not all possible drugs interactions are so serious that the drugs cannot be taken together. 'To clarify the relevance of an interaction in an individual case, the pharmacist looks at the medications involved and speaks with the doctor and patient,' Fink said.

Depending on the degree of the interaction, the pharmacist either recommends that the medications not be taken simultaneously or that regular checks be made for possible health consequences.