by Bell H

Over-the-Counter Drugs: Follow the Instructions

IMAGE Many people think over-the-counter (OTC) drugs are harmless, but they can be harmful if misused. Read on to learn about some common examples.


Stimulant-type laxatives are among the most misused OTC medications. Their active ingredients work by irritating the lining of the intestine. They are often misused by people trying to lose weight, but the people most affected by laxative misuse may be the elderly in nursing homes.
People who take laxatives too often to prevent or treat constipation may become dependent on them in order to have a normal bowel movement.
A different form of laxative overuse, intake to the point of diarrhea, may lead to the following complications:
  • Malnutrition—your body cannot absorb certain nutrients before they leave your body.
  • Dehydration—which will also worsen your constipation .
  • Sodium and potassium deficiencies—can affect a wide range of body systems, including the heart and nervous system.
  • Calcium depletion—can contribute to an increased risk for fractures.

Sleeping Pills

Most OTC sleep aids contain antihistamines to cause drowsiness. Often, they lose effectiveness over time, which prompts people to take more than the recommended dose. Some people develop a psychological dependence.
Next-day drowsiness is a common problem with OTC sleep aids, even when taken as directed. Many people feel drowsy for longer than 8 hours after taking them. Overuse of OTC sleep aids can also cause the following symptoms:
  • Lightheadedness
  • Disturbed coordination
  • Abdominal pain
  • Thickening of bronchial secretions
People with glaucoma, respiratory conditions, or difficulty urinating should talk to their doctor before using products containing an antihistamine.


Taking OTC pain relievers can be harmful if you take too many for too long. Commonly used nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen can cause the following when used too often for too long:
  • Ulcers, which may bleed
  • Kidney damage
  • Liver damage
NSAIDs may also increase the risk of having a heart attack or stroke. This risk may increase with longer use.

How Much is Too Much?

To be safe, carefully follow the package directions or your doctor's advice when taking NSAIDs. Taking too much of these medications can increase your risk of these adverse effects, especially if you are older.


Acetaminophen, a widely used pain reliever, may cause liver damage if used improperly.
As with NSAIDs, do not to take more than the recommended dose on the acetaminophen label. Also, do not take this medication for more days than recommended. It is important to keep in mind that taking more than the recommended dose will not result in added relief.
Remember that acetaminophen and NSAIDs are in many OTC cough and cold remedies. Also, acetaminophen is in some prescription pain medications like percocet and vicodin. So watch to make sure that you are not getting extra amounts of acetaminophen from other sources.
Talk to your doctor before using acetaminophen or NSAIDs if you have liver disease, are on warfarin therapy, drink more than 3 alcoholic beverages per day, or are taking other OTC or prescription medications.
Over-the-counter drugs are generally safe, but if you ignore the package directions or your doctor's recommendations, there can be dangerous consequences.


Family Doctor—American Academy of Family Physicians
Food and Drug Administration


Health Canada
Healthy Alberta


Acetaminophen. EBSCO DynaMed website. Available at: Updated April 6, 2016. Accessed April 14, 2016.
Diphenhydramine. EBSCO DynaMed website. Available at: Updated April 6, 2016. Accessed April 14, 2016.
Health hints: use caution with pain relievers. Food and Drug Administration website. Available at: Updated March 25, 2016. Accessed April 14, 2016.
Hypocalcemia. EBSCO DynaMed website. Available at: Updated June 2, 2014. Accessed April 14, 2016.
Mounsey A, Raleigh M, Wilson A. Management of constipation in older adults. Am Fam Physician. 2015;92(6):500-504.
Naproxen. EBSCO DynaMed website. Available at: Updated April 6, 2016. Accessed April 14, 2016.
Pain relievers: Understanding Your OTC Options. American Academy of Family Physicians Family Doctor website. Available at: Updated October 2013. Accessed April 14, 2016.
Side effects of sleep drugs. US Food and Drug Administration website. Available at: Updated April 11, 2016. Accessed April 14, 2016.

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