2. Muscle relaxants

Be cautious of: cyclobenzaprine (Flexeril), methocarbamol (Robaxin), carisoprodol (Soma) and similar medications.

The concern: These medications can leave you feeling groggy and confused, increase your risk of falls, and cause constipation, dry mouth and urination problems. Plus, there's little evidence that they work well.

3. Anti-anxiety and anti-insomnia drugs

Be cautious of: benzodiazepines, such as diazepam (Valium), alprazolam (Xanax) or chlordiazepoxide (Librium, Limbitrol, Librax) as well as nonbenzodiazepine sleeping pills, such as zaleplon (Sonata) and zolpidem (Ambien).

The concern: In older adults especially, these medications can increase your risk of falls, as well as cause confusion. Because it takes your body a long time to get these drugs out of your system, you could feel groggy and sleepy for an extended period of time.

4. Anticholinergic Drugs

Be cautious of: medications including the antidepressants amitriptyline (Elavil) and imipramine (Tofranil), the anti-Parkinson's drug trihexyphenidyl (Artane), the irritable bowel syndrome drug dicyclomine (Bentyl), the overactive bladder drug oxybutynin (Ditropan) and diphenhydramine, an antihistamine (Benadryl) often included in over-the-counter sleep medicines such as Tylenol PM.

The concern: Anticholinergic drugs can cause confusion, constipation, urination problems, blurry vision and low blood pressure.

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