In a trans male patient with a hysterectomy who is experiencing vasomotor hot flashes, what is the appropriate management strategy and is fezolinetant (Veozah) an appropriate treatment option?

Management of Vasomotor Symptoms in Trans Male Patients Post-Hysterectomy

For a trans male patient with hysterectomy experiencing hot flashes, first-line management should be testosterone optimization if the patient is on gender-affirming hormone therapy (GAHT), followed by non-hormonal pharmacologic options including SSRIs/SNRIs, gabapentin, or fezolinetant (Veozah) if symptoms persist despite adequate testosterone levels.

Initial Assessment and Testosterone Optimization

Before considering additional treatments, verify the patient's testosterone levels. Trans men on GAHT should have testosterone levels in the typical physiological range for cisgender men (300-1,000 ng/dL) 1. Check morning total and free testosterone levels, as inadequate testosterone replacement can contribute to vasomotor symptoms 2.

If testosterone levels are suboptimal:

• Adjust GAHT dosing or formulation
• Consider switching from injectable esters to alternative delivery methods (gels, patches, or long-acting testosterone undecanoate) 1
• Re-evaluate after 4-6 weeks of optimized therapy

Non-Hormonal Pharmacologic Management

When vasomotor symptoms persist despite adequate testosterone levels, or if the patient is not on GAHT, non-hormonal options are appropriate:

First-Line Non-Hormonal Options

Antidepressants (most evidence-based):

• Venlafaxine (SNRI): Most studied, effective for symptom reduction 3, 2
• Paroxetine (SSRI): FDA-approved specifically for vasomotor symptoms at low doses 4

Gabapentin: Demonstrated efficacy comparable to venlafaxine 2

Fezolinetant (Veozah): Appropriate and effective option 5

Fezolinetant Considerations

Yes, fezolinetant (Veozah) would work for this patient. It is FDA-approved for moderate to severe vasomotor symptoms due to menopause and is not a hormone 5. The mechanism targets neurokinin 3 receptors in the hypothalamus, directly addressing the thermoregulatory dysfunction causing hot flashes 6, 7.

Efficacy: Fezolinetant 45 mg daily significantly reduces both frequency (mean reduction of 2.55 hot flashes/day vs placebo at week 12) and severity of vasomotor symptoms, with improvements observed within 1 week and maintained over 52 weeks 6, 8.

Critical Safety Requirements 5:

• Baseline liver function tests (ALT, AST, ALP, total and direct bilirubin) are mandatory before starting
• Do NOT start if ALT or AST ≥2× ULN or total bilirubin ≥2× ULN
• Monthly liver monitoring for first 3 months, then at 6 and 9 months
• Contraindicated in cirrhosis or severe renal impairment
• Contraindicated with CYP1A2 inhibitors

Dosing: 45 mg orally once daily, taken whole with liquids 5

Common adverse effects: Abdominal pain, diarrhea, insomnia, back pain (37-43% overall TEAE rate, similar to placebo) 6, 8

Important caveat: Hepatotoxicity has occurred in postmarketing surveillance, with cases of drug-induced liver injury within 40 days of starting treatment 5. Patients must immediately discontinue and seek medical attention if experiencing fatigue, nausea, jaundice, dark urine, or abdominal pain.

Alternative Non-Hormonal Options

If fezolinetant is not suitable or preferred:

Medroxyprogesterone acetate or cyproterone acetate: Effective for vasomotor symptoms in patients on androgen deprivation therapy 3

Oxybutynin: Another option with evidence for vasomotor symptom reduction 4

Non-Pharmacologic Interventions

Cognitive Behavioral Therapy (CBT): Reduces perceived burden of hot flashes and should be offered 2

Acupuncture: Equivalent to or better than venlafaxine or gabapentin in some studies 2

Lifestyle modifications 2:

• Weight loss (≥10% body weight) if BMI elevated
• Smoking cessation
• Limiting alcohol if it triggers symptoms
• Regular physical activity (for overall health, though not specifically proven for vasomotor symptoms)

Clinical Pitfalls to Avoid

1. Do not assume vasomotor symptoms are solely menopause-related: Rule out thyroid disease, diabetes, pheochromocytoma, and carcinoid syndrome 9, 2

2. FSH is unreliable in trans men with prior chemotherapy or pelvic radiation 2

3. Do not use estrogen-based menopausal hormone therapy in trans male patients, as this contradicts their gender-affirming care goals

4. Monitor liver function religiously with fezolinetant: The hepatotoxicity risk, while low (2.3% with transaminase elevations >3× ULN), requires strict adherence to monitoring protocols 5, 6, 8

5. Verify medication interactions: Fezolinetant is contraindicated with CYP1A2 inhibitors (e.g., fluvoxamine, ciprofloxacin) 5

Treatment Algorithm Summary

1. Optimize testosterone (if on GAHT) → target 300-1,000 ng/dL
2. If symptoms persist or patient not on GAHT:
   • Consider venlafaxine, paroxetine, or gabapentin as first-line
   • Fezolinetant 45 mg daily is an excellent alternative if:
     • Baseline liver function is normal
     • Patient can comply with monitoring requirements
     • No contraindications present
3. Add CBT or acupuncture as adjunctive therapy
4. Implement lifestyle modifications concurrently

The choice between these options should consider patient preference, contraindications, monitoring burden, and cost, but fezolinetant represents a highly effective non-hormonal option specifically designed for vasomotor symptoms 6, 4, 7.