9. Incontinence drugs (Anticholinergics)
Why they are prescribed: These medications are used to relieve symptoms of overactive bladder and reduce episodes of urge incontinence, an urge to urinate so sudden and strong that you often can't get to a bathroom in time.
Examples: Darifenacin (Enablex), oxybutynin (Ditropan XL, Gelnique, Oxytrol), solifenacin (Vesicare), tolterodine (Detrol) and trospium (Sanctura). Another oxybutynin product, Oxytrol for Women, is sold over the counter.
How they can cause memory loss: These drugs block the action of acetylcholine, a chemical messenger that mediates all sorts of functions in the body. In the bladder, anticholinergics prevent involuntary contractions of the muscles that control urine flow. In the brain, they inhibit activity in the memory and learning centers. The risk of memory loss is heightened when the drugs are taken for more than a short time or used with other anticholinergic drugs.
A 2006 study of oxybutynin ER, for example, found its effect on memory to be comparable to about 10 years of cognitive aging. ("In other words," as the study's lead author put it, "we transformed these people from functioning like 67-year-olds to 77-year-olds.")
Older people are particularly vulnerable to the other adverse effects of anticholinergic drugs, including constipation (which, in turn, can cause urinary incontinence), blurred vision, dizziness, anxiety, depression and hallucinations.
Alternatives: As a first step, it's important to make sure that you have been properly diagnosed. Check with your doctor or other health professional to see if your urinary incontinence symptoms might stem from another condition (such as a bladder infection or another form of incontinence) or a medication (such as a blood pressure drug, diuretic or muscle relaxant).
Once these are ruled out, I'd recommend trying some simple lifestyle changes, such as cutting back on caffeinated and alcoholic beverages, drinking less before bedtime, and doing Kegel exercises to strengthen the pelvic muscles that help control urination.
If these approaches don't work out, consider trying adult diapers, pads or panty liners, which can be purchased just about anywhere. They can be worn comfortably (and invisibly) under everyday clothing and virtually eliminate the risk of embarrassing accidents. In my experience, many patients are reluctant to try this approach, but once over the initial hurdle, come to prefer it for security and peace of mind.
Correction: An earlier version of this article mistakenly implied that mirabegron (Myrbetriq), which the FDA approved last year for the treatment of overactive bladder, is an anticholinergic drug; in fact, it is in a new class of medications called beta-3 adrenergic agonists and is not expected to cause memory loss seen with anticholinergic medications. There currently are no data describing the effect of Myrbetriq on cognition.
10. Antihistamines (First-generation)
Why they are prescribed: These medications are used to relieve or prevent allergy symptoms or those of the common cold. Some antihistamines are also used to prevent motion sickness, nausea, vomiting and dizziness, and to treat anxiety or insomnia.
Examples: Brompheniramine (Dimetane), carbinoxamine (Clistin), chlorpheniramine (Chlor-Trimeton), clemastine (Tavist), diphenhydramine (Benadryl) and hydroxyzine (Vistaril).
How they can cause memory loss: These medications (prescription and over-the-counter) inhibit the action of acetylcholine, a chemical messenger that mediates a wide range of functions in the body. In the brain, they inhibit activity in the memory and learning centers, which can lead to memory loss.
Alternatives: Newer-generation antihistamines such as loratadine (Claritin) and cetirizine (Zyrtec) are better tolerated by older patients and do not present the same risks to memory and cognition.
Ask the Pharmacist is written by Armon B. Neel Jr., PharmD, CGP, in collaboration with journalist Bill Hogan. They are coauthors of Are Your Prescriptions Killing You? (Atria Books).