Which medications can cause amnesia or tremors among levothyroxine, propranolol, lamotrigine, bupropion, baclofen, metformin, spironolactone, ezetimibe, minoxidil, progesterone, Pepcid (famotidine), omeprazole, Lunesta (eszopiclone), and alprazolam?

Medications That Can Cause Amnesia or Tremor

Among the listed medications, propranolol, lamotrigine, bupropion, baclofen, alprazolam, and eszopiclone (Lunesta) can cause amnesia or tremor as side effects.

Medications That Can Cause Tremor

Beta-Blockers

• Propranolol can cause tremor, particularly when withdrawn, as it is commonly used to treat essential tremor; paradoxically, withdrawal can exacerbate tremor symptoms 1, 2
• Tremor is listed as a potential adverse effect when propranolol is used with levodopa or amantadine due to cumulative dopamine agonist effects 3

Antidepressants

• Bupropion can cause tremor as part of its side effect profile, particularly related to its dopaminergic effects 1, 3
• Tremor is specifically listed among the common nervous system adverse reactions with bupropion 3

Anticonvulsants

• Lamotrigine can cause tremor as a side effect, though it is generally considered more weight-neutral and has fewer tremor-inducing properties compared to other anticonvulsants like valproic acid 1

Muscle Relaxants

• Baclofen can cause tremor, particularly when used in patients with sleep apnea, and may affect central nervous system function 1

Benzodiazepines

• Alprazolam can cause tremor, particularly during withdrawal periods 1
• Paradoxically, benzodiazepines like alprazolam are sometimes used to treat tremor, but can cause tremor as a withdrawal symptom 2, 4

Medications That Can Cause Amnesia

Benzodiazepines

• Alprazolam is strongly associated with amnesia, which is listed as a potential adverse effect in the nervous system category 3

Sedative-Hypnotics

• Eszopiclone (Lunesta) can cause amnesia as it affects memory consolidation similar to other sleep medications 1

Anticonvulsants

• Lamotrigine has been associated with memory issues, though less commonly than other anticonvulsants 1

Medications Less Likely to Cause Amnesia or Tremor

• Levothyroxine - while hyperthyroidism can cause tremor, therapeutic doses of levothyroxine typically don't cause tremor unless overdosed 1
• Metformin - not commonly associated with either amnesia or tremor 1
• Spironolactone - not typically associated with amnesia or tremor 1
• Ezetimibe - not commonly associated with amnesia or tremor 1
• Minoxidil - not typically associated with amnesia or tremor 1
• Progesterone - not commonly associated with amnesia or tremor 1
• Famotidine (Pepcid) - not typically associated with amnesia or tremor 1
• Omeprazole - not commonly associated with amnesia or tremor 1

Clinical Considerations

Risk Factors That Increase Likelihood of Side Effects

• Elderly patients are more susceptible to medication-induced amnesia, particularly with benzodiazepines like alprazolam 1
• Patients with existing neurological conditions may experience worsened tremor with medications like bupropion 3
• Concomitant use of multiple CNS-active medications increases risk of both amnesia and tremor 3

Management Recommendations

• For patients requiring medications with tremor risk, consider alternatives when possible (e.g., alternative beta-blockers with less tremor potential) 1, 2
• Monitor for early signs of cognitive effects when using alprazolam or eszopiclone, particularly in elderly patients 1
• When prescribing bupropion, start with lower doses and titrate slowly to minimize tremor risk 1, 3
• Avoid abrupt discontinuation of propranolol, alprazolam, or baclofen as this can precipitate or worsen tremor 2, 4

Special Populations

Elderly Patients

• Elderly patients are at higher risk for both amnesia and tremor with these medications, particularly with benzodiazepines 1
• Lower starting doses and careful monitoring are recommended for bupropion, alprazolam, and eszopiclone in elderly patients 1, 3

Patients with Neurological Conditions

• Patients with pre-existing tremor disorders should use bupropion with caution 3
• Patients with seizure disorders should avoid bupropion as it can lower seizure threshold and potentially worsen neurological symptoms 1, 3

Remember that individual patient factors, dosing, and drug interactions can significantly influence the likelihood and severity of these side effects.