Types of Medication that Can Cause Memory Loss
The following 10 categories of drugs can potentially cause memory loss by depressing chemical signals in the nervous system.
Tranquilizers slow down the speed at which messages travel between nerve cells. For this reason, this category of medications is used to slow down the brain to induce sleep, decrease irritability during seizure activity, and slow the hyper-reactive brain cell responses that cause anxiety. These slowing effects also produce anticholinergic effects which dry up secretions. The amount of cerebral spinal fluid, which cushions and bathes the brain in neurotransmitters, may be affected.
2. Anti-Cholesterol Drugs
White matter and nerve-insulating myelin sheath in the brain make up one-fourth of the total cholesterol in the body. Oral anti-cholesterol medications are meant to lower your serum levels of LDL (Low-Density Lipids.) Since the medication crosses over the blood-brain barrier, the cholesterol-lowering mechanism decreases cholesterol in the brain, as well as in the rest of the body. Under-insulated nerve cells are less protected and are more likely to “short out,” or malfunction.
3. Anti-Seizure Drugs (AED)
Anti-seizure drugs are used to treat chronic pain, seizures, bipolar or mood disorders, an mania associated with hyper-impulsivity and insomnia. Similar to tranquilizers, these medications dampen down or decrease the speed of transmission, thus causing memory loss.
4. Tricyclic Antidepressants
Tricyclic antidepressants (TCA) are used for anxiety and depression, chronic pain, Obsessive-Compulsive Disorder (OCD), and even smoking cessation. TCA blocks the action of norepinephrine and serotonin, two of the key neurotransmitters that transmit electrical impulses in the brain. Impairment in their levels dampens electrical transmission of neural information. As a result, 35% of TCA patients experience memory impairment, and 54% experience impaired concentration.
5. Narcotic Painkillers
Opiates are used to relieve moderate to severe chronic pain conditions such as rheumatoid arthritis. Opioids operate by stemming the flow of pain signals within the central nervous system and numbing the individual’s response to pain. Both the decreasing pain signals and the numbed emotional response are mediated by the neurotransmitters which are involved in cognition. This can interfere with long and short-term memory, especially with extended use of the drugs.
6. Parkinson’s Drugs (Dopamine Agonists)
Dopamine agonists can be prescribed for Parkinsonism, as well as certain pituitary tumors, and restless leg syndrome. The chemical messenger dopamine is responsible for multiple brain functions including motivation, pleasure, fine motor control, learning, and memory. The major side effects of Dopamine Agonists include memory loss, delusions, confusion, hallucinations, drowsiness, and compulsive behaviors such as overeating and gambling, which may result from the person failing to remember how much they have already eaten or spent.
7. Antihypertensive Drugs (Beta Blockers)
Beta-blockers slow the heart rate and reduce blood pressure for conditions such as congestive heart failure, chest pain, migraines, tremors, high blood pressure, or cardiac arrthythmias. They are also used in eye drops for glaucoma-high intraocular pressures. These beta-blockers interfere with memory by blocking the actions of norepinephrine and epinephrine neurotransmitters.
8. Sleeping Aids (Nonbenzodiazepines)
Nonbenzodiazepines sleeping aids, which include Lunesta, Sonata, and Ambien, among others, act on many of the same pathways and neurotransmitters as tranquilizers or benzodiazepines. They produce similar side effects and problems with tolerance and withdrawal. These “Z” (meaning sleep) drugs can cause amnesia, and, in some consumers, trigger potentially highly risky behaviors, such as cooking or driving a car while sleep-walking with no memory of having done so.
9. Incontinence Medications (Anticholinergics)
Overactive bladders cause an urgency to urinate so suddenly that the individual may not be able to get to the bathroom fast enough. Medications used to treat this block the action of acetycholine, thus preventing involuntary contractions of the muscles that control urine flow. Anticholinergics affect the brain by inhibiting memory and learning centers increasingly the longer the person is taking the drugs. A 2006 study of Oxybutynin Extended Release suggested that older people (average age 67) are more vulnerable to the side effects such as profound memory loss, blurred vision, dizziness, anxiety, depression, and hallucinations. It was found that those who had been taking Oxybutynin had cognitive functioning comparable to that of 77-year-olds.
10. Antihistamines (First Generation)
Antihistamines are used to decrease allergy symptoms, motion sickness, nausea, vomiting, anxiety, and insomnia. Over-the-counter and prescription-strength antihistamines inhibit the action of acetylcholine, thus affecting the retrieval mechanism of neurotransmitters for memory and learning.
The above is a summary of the following article:
Neel, Dr. Armon B, “Caution! These 10 Drugs Can Cause Memory Loss,” “Ask the Pharmacist” Column, February 9, 2016.
Available at https://www.aarp.org/health/drugs-supplements/info-2017/caution-these-10-drugs-can-cause-memory-loss.html