So much news is made of the occurrence and prevalence of diseases such as cancer and AIDS; and of viruses such as Bird Flu and SARS that one could be easily be mistaken in thinking that humans are a species at risk. Although some of these possible pandemics are a sobering thought, you may take solace in the fact that we have a smaller chance of getting, and a better chance of beating, a damning diagnosis than ever before. In part, this has been achieved through the dual advance of the pharmaceutical and nutritional sciences: we have an arsenal of both nutraceuticals and drugs for prevention, treatment and cure.
At the last big count, 7.5% of Americans aged 18 to 44 take 3 or more prescribed drugs, this rises to a huge 47.6% in those aged 65 or over. At the same time over a third of the US population uses dietary supplements daily and over 20% have used some form of natural product in the past 12 months. When these statistics are put together it would be safe to assume that many people are on at least one drug and at least one nutraceuticals at the same time. A recent study also estimated that 70% of patients fail to tell their doctor they are undergoing alternative treatment for their problems. Problems like depression, asthma, diabetes, arthritis, allergies, flu and high blood pressure are now so well characterized and supported by drugs that physicians may feel less inclined to investigate the condition, or the person, further.
Side effects of drugs are well known with huge legal cases such as Vioxx bringing the industry and the regulation process into the spotlight. Drug-drug interactions are also well documented and millions of dollars are spent on research and testing to find out exactly what can, and can't, be used concomitantly. However, when it comes to nutraceuticals, few people have much, if any, knowledge about what happens in the body when you take these with prescription medicine. And with scant formal training for herbal products or nutraceuticals in medical school, your doctor may be more in the dark than you are.
Drug Supplements Interactions - Two Rights Can Make a Wrong
Many drugs are cleared from the body by certain enzymes in the liver, especially those from a certain family called cytochrome P450s. These enzymes may also be responsible for breaking down other substances, such as alcohol, nutrients and herbal products. These particular enzymes can be held up by breaking down a nutraceutical you have ingested, while the drug will be circulating in your bloodstream a lot longer than the physician had planned. If you are taking multiple doses of the drug then it can build up to dangerous levels, and if the drug has a narrow window between good effects and harm then overdose is a distinct possibility.
A good example is Digoxin, a cardiovascular drug. If Digoxin is taken with licorice, the levels of the drug in the bloodstream can be increased four fold, the effects and side effects will be increased dramatically to a possibly lethal endpoint.
Drugs and vitamins, herbs or nutraceuticals can also have a synergic effect when taken together. They may produce the same reaction in your body or interact in some way to produce unexpected and undesirable results. This can happen with the anti-anxiety drug, Alprazolam or Xanax. When Xanax is taken with the popular herb Kava, also used for anxiety, they can have a drastic effect upon the central nervous system. The reasons are not fully understood but at least one person has been hospitalized with severe mental problems by taking this combination.
Nutraceuticals may also have the opposite effect on these P450 enzymes and they can have what is called an "inductive effect" whereby the nutraceutical boosts the activity of the enzyme to higher than normal levels. The enzyme then breaks down and clears the drug from the body much faster than was expected by your physician. Because the dose of a drug is a very exact calculation, a prescribed amount is designed to stay in the body for a time long enough to be effective. If the drug is cleared early it may have a reduced effect or no effect at all.
Further Information on Drug Dietary Supplement Interactions
You should first and foremost tell your doctor and pharmacist what you are taking. Unfortunately, there is not a high level of understanding in the medical or pharmaceutical world into herbs and nutraceuticals although some research has been conducted into the popular herbs such as St. John's Wort, Ginseng, Gingko, Cayenne, Saw Palmetto and Valerian. A dietician may have better knowledge than your doctor but there are also a number of sources of information concerning prescription drug-dietary supplement interactions on the internet below.
The http://www.merck.com/mmhe/sec02/ch019/ch019a.html">Merck Manual is a comprehensive resource of up to date medical information and has some good primers on interactions as well as in depth analysis.
The National Institute of Health's Office of Dietary Supplements has a number of good fact sheets on different supplements
Mitamins is an online retailer of custom multivitamins and offers a free drug interaction checker. The website allows the design of a custom multivitamin according to the prescription drugs you are taking. An online library also allows two-way reviewing of drugs or supplements, listing the type of interactions.