Risks of Over-the-counter Meds
Posted on November 30, 2014 by bob in In Every Life
Over the past few months, the importance of evaluating health information in the media has been discussed in this column. Manufacturers of over-the-counter (OTC) products present potential benefits, but it is often difficult to evaluate if you should purchase these to meet your needs, or if possible risks outweigh potential benefits. The plethora of advertisements for products classified as complementary or alternative medicines (CAM) is of particular concern.
The term “complementary” refers to a product or treatment used in conjunction with another one. “Alternative” refers to 
products or treatments used instead of other(s). One risk of CAM treatments is termed opportunity cost–the potential of losing the opportunity for another treatment that may be effective only during a specific time within the course of an illness. Another risk involves potential interactions with concurrent prescribed medications.
Products classified as CAM are evaluated by the Food and Drug Administration (FDA) using different criteria than for pharmaceuticals, which contributes to variations in their strength. Some manufacturers label their products as independently monitored for strength and quality, but the amount per dose can vary, making comparative research difficult. This variability also makes predicting potential interactions with other medicines or treatments difficult. Further information can be obtained at the FDA website. See http://www.fda.gov/forconsumers/consumerupdates/ucm118079.htm
Two additional risks of CAM are the lack of large peer-reviewed research that provides evidence of the treatment’s effectiveness, and lack of knowledge about how a CAM treatment may interact with other ongoing treatments. The National Institutes of Health (NIH) has a repository of information about CAM at the National Center for Complementary and Alternative Medicine (NCCAM). See http://nccam.nih.gov/
Potential for altering effectiveness of concurrent products is based on the principle that all substances taken into or applied to the body go through four processes:
1) Absorption
2) Metabolism
3) Distribution
4) Excretion
Each person’s body functions uniquely, and the time for completing each of these processes varies, making it difficult to predict how any product will be processed. Changes that accompany aging affect the length of time for these processes to be completed, posing a risk that one dose may not be fully metabolized, distributed, or excreted by the time the next dose is taken, leading to overdosing and further complications. An additional concern is that one substance may block absorption of another, or possibly increase the action of each product.
For example, the actions of anti-coagulant medications such as Coumadin are increased by supplements such as Gingko, potentially leading to hemorrhage. Furthermore, variations in strength complicate the risk for interacting or interfering with other substances or body functions.
Another example is Benadryl, an OTC antihistamine that can be purchased in varying strengths. It is also marketed as a sleep aid due to its side effect of drowsiness. However, its antihistamine properties can reduce bodily fluids and cause confusion or dizziness. A list compiled by Dr. Mark Beers is available to review medications that are of higher risk for older adults. See http://www.ngna.org/_resources/documentation/chapter/carolina_mountain/Beers%20Criteria%20Literature.pdf
Although a product may be effective for one person, it may not work that way for you. All products and treatments should be listed with times, doses and intended purposes and discussed with healthcare providers at each visit. OTC medications are convenient, but they do pose risks. If you are considering adding a product, discuss this first to avoid interactions or complications.
Arlene Morris
Arlene H. Morris, EdD, RN, CNE, is Professor of Nursing, Auburn Montgomery School of Nursing, and Immediate Past President of the AL State Nurses Association. Reach her at amorris@aum.edu.
