Medicinal advancements have been effective in treating illness and disease. Usage is at an all-time high, creating heightened risks for potential errors. Newly approved prescription products continue entering the market, generic alternatives are increasingly available, and over-the-counter (OTC) products are now touted as “available without a prescription” or as “prescription-strength”. Many people take multiple prescription medications, non-prescription products, supplements and herbal remedies compounding the potential for harmful drug interactions. The Institute of Medicine says approximately 1.5 million medication-related errors and 7,000 deaths occur annually in U.S. hospitals from mistakes.
Three Types of Interactions
- Duplicating effects: Occurs from taking multiple drugs with comparable ingredients resulting in a higher intensity dosage and effect. A common example is taking OTC ibuprofen with anti-inflammatory prescription products.
- Opposing products: Medications containing active ingredients having opposite effects potentially neutralize the efficacy of both. For example, many OTC cold products elevate blood pressure and counteract prescription hypertension products.
- Alteration: Occurs when one drug alters the manner the body absorbs, transports, or metabolizes drugs in your system leading to potential adverse reactions.
Who is Most at Risk for Harmful Drug Interactions?
Certain patient classifications are at a higher risk, including those with chronic health-related conditions like diabetics, those with high blood pressure, or heart disease. They are likely taking drugs daily for their conditions. Older people are at high risk because they are the largest medication consumers and experience physical changes from aging that heighten interactional risks. Roughly 40% of those ages 65 or older are on a regimen of five or more products. Children (pediatric) are frequent users of OTC medications, often without consulting a doctor, and are naturally more affected by even small drug dosages.
Common OTC Problems
OTC products generally contain labeling and information about ingredients, warnings, and potential interactions. Many interactional warnings do not specify drugs by name but rather based on the conditions they treat. For example, “this product should not be taken with sedatives or tranquilizers”. In these instances, it is critical to understand the types of prescription products from your doctor and reasons why they are prescribed. Some OTC products with possible interactional problems include:
- Decongestants: Brands include Sudafed, Mucinex, and Dimetapp. They may not be advised for those taking blood pressure medications (hypertension) or MAOIs such as Isocarboxazid (Marplan), Phenelzine (Nardil), or Selegiline (Emsam)
- Dextromethorphan: Cough treatment brands including Delsym, Robitussin, and Vicks DayQuil Cough may be harmful when used with MAOIs, or those containing pseudoephedrine.
- Antihistamines: Common brands are Benadryl, Allegra, and Zyrtec that should not be taken with alcohol, anti-anxiety medications, or opioids.
Physician Medical Liability Concerns
According to the Doctors Company, a large medical malpractice insurer, physicians typically have a duty to warn those they prescribe medications regarding hazards and complications. Manufacturers of drug products are also required to do so. Physicians may be considered “learned intermediaries” creating potential liability when the patient is not warned about potential dangers. Doctors should ask patients to disclose OTC, supplement, herbal, and other products prescribed by other physicians to check for potential interactions.