3. Antiseizure drugs
Why they are prescribed: Long used to treat seizures, these medications are increasingly prescribed for nerve pain, bipolar disorder, mood disorders and mania.
Examples: Acetazolamide (Diamox), carbamazepine (Tegretol), ezogabine (Potiga), gabapentin (Neurontin), lamotrigine (Lamictal), levetiracetam (Keppra), oxcarbazepine (Trileptal), pregabalin (Lyrica), rufinamide (Banzel), topiramate (Topamax), valproic acid (Depakote) and zonisamide (Zonegran).
How they can cause memory loss: Anticonvulsants are believed to limit seizures by dampening the flow of signals within the central nervous system (CNS). All drugs that depress signaling in the CNS can cause memory loss.
Alternatives: Many patients with seizures do well on phenytoin (Dilantin), which has little if any impact on memory. Many patients with chronic nerve pain find that venlafaxine (Effexor) — which also spares memory — alleviates their pain.
4. Antidepressant drugs (Tricyclic antidepressants)
Why they are prescribed: TCAs are prescribed for depression and, increasingly, anxiety disorders, eating disorders, obsessive-compulsive disorder, chronic pain, smoking cessation and some hormone-mediated disorders, such as severe menstrual cramps and hot flashes.
Examples: Amitriptyline (Elavil), clomipramine (Anafranil), desipramine (Norpramin), doxepin (Sinequan), imipramine (Tofranil), nortriptyline (Pamelor), protriptyline (Vivactil) and trimipramine (Surmontil).
How they can cause memory loss: About 35 percent of adults taking TCAs report some degree of memory impairment and about 54 percent report having difficulty concentrating. TCAs are thought to cause memory problems by blocking the action of serotonin and norepinephrine — two of the brain's key chemical messengers.
Alternatives: Talk with your health care provider about whether nondrug therapies might work just as well or better for you than a drug. You might also want to explore lowering your dose (the side effects of antidepressants are often dose-related) or switching to a selective serotonin/norepinephrine reuptake inhibitor (SSRI/SNRI). Of the drugs in this category, I find venlafaxine (Effexor) to have the fewest adverse side effects in older patients.
5. Narcotic painkillers
Why they are prescribed: Also called opioid analgesics, these medications are used to relieve moderate to severe chronic pain, such as the pain caused by rheumatoid arthritis.
Examples: Fentanyl (Duragesic), hydrocodone (Norco, Vicodin), hydromorphone (Dilaudid, Exalgo), morphine (Astramorph, Avinza) and oxycodone (OxyContin, Percocet). These drugs come in many different forms, including tablets, solutions for injection, transdermal patches and suppositories.
How they can cause memory loss: These drugs work by stemming the flow of pain signals within the central nervous system and by blunting one's emotional reaction to pain. Both these actions are mediated by chemical messengers that are also involved in many aspects of cognition. So use of these drugs can interfere with long- and short-term memory, especially when used for extended periods of time.
Alternatives: In patients under the age of 50 years, nonsteroidal anti-inflammatory drugs (NSAIDs) are the frontline therapy for pain. Unfortunately, NSAID therapy is less appropriate for older patients, who have a much higher risk of dangerous gastrointestinal bleeding. Research shows the risk goes up with the dosage and duration of treatment.
Talk with your doctor or other health care provider about whether tramadol (Ultram), a nonnarcotic painkiller, might be a good choice for you. In my practice, I often recommend supplementing each 50 mg dose with a 325 mg tablet of acetaminophen (Tylenol). While there are prescription drugs that combine tramadol and acetaminophen, these products have only 37.5 mg of tramadol, and in my practice I've found that patients generally need the larger dose.
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