Doctor’s role key in preventing drug interaction

By Laura Mead
ESCANABA — With the endless choices of vitamins and supplements on the market these days, a trip to the medicine aisle can be overwhelming. Being educated and talking with a doctor is key in preventing drug interactions, even toxicity, say local physicians.

Dr. Patricia Parker, from Doctors Park Family Care in Escanaba, said it is more likely to take a vitamin or supplement that will interact with a prescription medication than to overdose on it.

Diane Kobasic, registered pharmacist at OSF St. Francis Hospital, said even standard vitamins can bind to common antibiotics, making them ineffective. Also, St. John’s Wort — an herbal supplement said to elevate mood — is known to interact with prescription anti-depressants, reducing or eliminating their effectiveness, she said.

This supplement can also inactivate birth control.

Both Parker and Kobasic advised consulting a physician before taking anything new and keeping them informed as to what you are already taking since vitamins and supplements can often interact with prescription medications. Kobasic also suggested taking vitamin/supplement bottles in with you to the doctor in case they are not familiar with it.

“If there’s a message clinicians would like to get out to the public it is you really need to approach medicines under one big umbrella,” said Parker. “Whether you think they’re important or not, they should always be mentioned to a clinician.”

Kobasic and Parker both also said a drug store pharmacist will have no problem looking at prescription records to determine whether the vitamin/supplement you want to purchase will interact with medications you’re already taking. While toxicity is rare, there are certain vitamins that people should be aware of. Kobasic and Parker said vitamins A, D, E, and K are fat soluble vitamins, meaning they are absorbed by the body’s fat cells and can accumulate, therefore they can cause toxicity if taken in too high of dosages.

Parker said there is really no need to take supplements of these vitamins with the exception of people with osteoporosis who take Vitamin D to help with calcium absorption. Parker said the body keeps a supply of A, E, and D stored in the liver for two months and people typically get enough from diet alone.

All other vitamins are water soluble, said Parker and Kobasic. With water soluble vitamins there isn’t danger of toxicity because the body excretes what it does not need.

While Parker said overdosing on even fat-soluble vitamins would be difficult, she said the best advice is to follow the guidelines on the back of the bottle or consult a physician or pharmacist before deciding to take more than what is recommended.

Kobasic said if someone were to overdose, toxicity could cause a range of effects to the skin, stomach and intestines, blood and liver, nerves, and lungs, depending on the vitamin. She said even if you’re not necessarily taking extreme amounts of a vitamin, taking amounts larger than recommended over a period of time can also cause toxicity. Assuming vitamins and supplements are harmless in any amount is a misconception, said Parker.

“People have the mistaken perception that if something is herbal or a supplement it can’t be bad for them.” “Often (the recommended dosage) is much lower than what people might be taking,” said Kobasic. “People think it’s just better to take more. If there’s a choice between grabbing the 50 mg tablets and the 1,000 mg, often they’ll take the 1,000 because they think, it’s got to be better.”

Another issue, said Kobasic, is companies who make over-the-counter medicines have no regulations as to how high of dosages they can manufacture.

“The FDA monitors and approves all prescription drugs,” she said. “The drug companies do tests and have to provide research that the drug is safe, but there’s no regulation for over the counters...companies can put in as much or as little as there’s a demand for.” However, Kobasic said there’s a government agency called United States Pharmacopeia (UPS) that does regulate the quality and purity of vitamins and supplements.

“If it says USP it’s at least a safer product, and manufacturers will designate this, she said.