GoodRx Health7 Medications That Can Make You Tired — And Why Your Antibiotic Isn’t One of Them

Medications That Cause Fatigue: Identifying Common Culprits and Understanding Their Impact

Fatigue is a prevalent issue affecting nearly half of the US population, often linked to various health conditions and medications. Although common medications such as antihistamines, muscle relaxers, and benzodiazepines are known to cause drowsiness, others like acetaminophen and antibiotics are not typically associated with this side effect. This article provides insights into the mechanisms by which certain medications induce fatigue and provides guidance for both patients and healthcare professionals on managing and mitigating these effects.

Key Points:

• Fatigue and Medications:
  • Fatigue can significantly impact daily activities, affecting up to 45% of people in the US
  • Several medications are known to cause drowsiness, including antihistamines, muscle relaxers, antidepressants, anti-seizure medications, beta blockers, opioids, and benzodiazepines.
• Antihistamines:
  • First-generation antihistamines, such as diphenhydramine (Benadryl) and doxylamine (Unisom SleepTabs), are more likely to cause drowsiness.
  • Second- and third-generation antihistamines, like fexofenadine (Allegra) and loratadine (Claritin), are less sedating.
  • Cetirizine (Zyrtec) may still cause drowsiness in some individuals.
• Muscle Relaxers:
  • Common muscle relaxants, such as cyclobenzaprine and tizanidine (Zanaflex), can induce significant drowsiness.
  • Metaxalone (Skelaxin) is a less sedating alternative.
• Antidepressants:
  • Fatigue is a potential side effect of many antidepressants, including trazodone, mirtazapine (Remeron), and tricyclic antidepressants (TCAs) like amitriptyline.
  • Selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs) can also cause drowsiness but to a lesser extent.
  • Adjusting dosage or timing, or switching to a different antidepressant like bupropion (Wellbutrin), may help manage fatigue.
• Anti-seizure Medications:
  • Medications like topiramate (Topamax), lamotrigine (Lamictal), and gabapentin (Neurontin) can cause drowsiness and dizziness.
  • Fatigue often improves as the body adjusts to the medication.
• Beta Blockers:
  • Used for heart conditions and migraine prevention, beta blockers like metoprolol (Toprol XL) and propranolol can cause fatigue.
  • Fatigue generally improves over time, but adjustments may be necessary if it persists.
• Opioids:
  • Opioid pain medications, including hydrocodone/acetaminophen (Norco) and oxycodone (Roxicodone), are highly sedating.
  • Combining opioids with acetaminophen does not contribute to drowsiness from the acetaminophen itself.
• Benzodiazepines:
  • Benzodiazepines (BZDs) like lorazepam (Ativan) and alprazolam (Xanax) can make patients feel sleepy, particularly when not used regularly.
  • Regular use may reduce drowsiness over time.
• Antibiotics:
  • Antibiotics such as amoxicillin and erythromycin do not cause drowsiness.
  • Fatigue during antibiotic treatment is likely due to the infection and the body’s immune response.
• Managing Drug-induced Fatigue:
  • Fatigue from medications may diminish as the body adjusts, but some medications will always cause drowsiness.
  • Patients should consult their healthcare team if fatigue persists, as medication adjustments may be necessary.

More than a third of Americans report getting less than seven hours of sleep in a 24-hour period. (NCOA)

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