What is the best course of treatment for a patient experiencing dizziness and unbalance after 6 months of taking finasteride (dutasteride) and a recent fall?

Evaluation and Management of Unbalance After Finasteride Use

The patient should discontinue finasteride immediately and undergo urgent evaluation for orthostatic hypotension and vestibular dysfunction, as dizziness and unbalance are not typical side effects of finasteride monotherapy and suggest either a concurrent medical condition or a rare neurological adverse effect.

Immediate Assessment Required

The clinical presentation of unbalance with a fall requires urgent evaluation because:

• Finasteride does not typically cause dizziness or balance problems as a primary adverse effect 1, 2
• The American Urological Association guidelines identify the primary adverse events of finasteride as sexual dysfunction (erectile dysfunction, decreased libido, ejaculatory problems), not vestibular or balance issues 1
• Dizziness and orthostatic hypotension are characteristic of alpha-blocker therapy (doxazosin, terazosin, tamsulosin), not 5-alpha reductase inhibitors like finasteride 1, 2

Differential Diagnosis to Evaluate

1. Concurrent Medication or Medical Condition

• Verify the patient is not also taking an alpha-blocker, as these commonly cause dizziness and postural hypotension 1, 2
• Assess for cardiovascular causes: orthostatic hypotension, arrhythmias, or other cardiac conditions
• Check for metabolic causes: hypoglycemia, electrolyte abnormalities

2. Rare Neurological Effects of Finasteride

• While not listed in standard guidelines, emerging evidence suggests finasteride can cross the blood-brain barrier and potentially affect neurosteroid production, leading to neurological symptoms 3
• Post-finasteride syndrome includes reports of cognitive changes and neurological dysfunction in some patients 4, 3

3. Vestibular or Central Nervous System Pathology

• The acute onset with a fall warrants evaluation for stroke, transient ischemic attack, or vestibular neuritis
• Consider brain imaging if neurological examination is abnormal

Management Algorithm

Step 1: Discontinue Finasteride

• Stop finasteride immediately given the temporal association with symptoms and the potential for persistent adverse effects 5, 4
• Sexual dysfunction side effects typically resolve after discontinuation, though the timeline is not specifically defined 5
• In rare cases (approximately 4-20% in some series), adverse effects may persist for months to years after stopping the medication 4, 3

Step 2: Perform Targeted Physical Examination

• Orthostatic vital signs: measure blood pressure and heart rate supine and after 1-3 minutes of standing
• Neurological examination: assess cranial nerves, cerebellar function (finger-to-nose, heel-to-shin, gait), and Romberg test
• Cardiovascular examination: assess for arrhythmias or murmurs

Step 3: Laboratory and Imaging Studies

• Basic metabolic panel, complete blood count
• If orthostatic hypotension is present without clear cause, consider endocrine evaluation
• Brain imaging (CT or MRI) if:
  • Focal neurological deficits present
  • Severe or progressive symptoms
  • Age >50 with new-onset balance problems and fall

Step 4: Specialist Referral if Symptoms Persist

• Neurology consultation if vestibular or central causes suspected
• Cardiology if cardiac etiology identified
• Consider psychiatry/mental health evaluation, as finasteride has been associated with neuropsychiatric effects including depression and suicidal ideation 6

Critical Caveats

• Do not assume finasteride is the cause without excluding serious conditions: The temporal association may be coincidental, and acute unbalance with falls requires thorough evaluation for stroke, cardiac arrhythmias, or other life-threatening conditions
• Monitor for persistent symptoms: If symptoms continue beyond 3 months after discontinuation, this may represent post-finasteride syndrome, which can be prolonged or permanent in rare cases 4, 3
• Screen for mental health symptoms: Recent FDA warnings highlight the association between finasteride and suicidal ideation; assess for depression or mood changes 6
• Document the adverse event: Report to FDA MedWatch if symptoms are severe or persistent

Alternative Treatment for Original Indication

If finasteride was prescribed for benign prostatic hyperplasia:

• Consider alpha-blocker monotherapy (though these cause more dizziness than finasteride) 1, 2
• Note that alpha-blockers have higher rates of dizziness and orthostatic hypotension compared to finasteride 1, 2

If prescribed for androgenetic alopecia:

• Discuss non-pharmacological options or topical treatments
• The risk-benefit ratio should be carefully reconsidered given this adverse event