37.3 Masculinizing Hormonal Therapy

Masculinizing Hormonal Therapy

Masculinizing hormonal therapy uses testosterone and related drugs to promote male secondary sex characteristics in transgender and nonbinary individuals. It's a cornerstone of gender-affirming care, and nurses need to understand the pharmacology, monitoring requirements, and client education involved in these treatments.

Key Characteristics and Actions of Masculinizing Hormonal Drugs

Testosterone is the primary masculinizing hormone. It's most commonly prescribed as an intramuscular injection using one of two ester formulations:

• Testosterone cypionate and testosterone enanthate are the most widely used forms. Both are long-acting esters given via IM injection, typically every 1–2 weeks (or subcutaneously in some protocols).
• Topical gels and transdermal patches are also available, though injections remain the most common route in gender-affirming care.

Testosterone promotes the development of male secondary sex characteristics:

• Deepening of the voice
• Facial and body hair growth
• Increased muscle mass and strength
• Redistribution of body fat (away from hips/thighs, toward the abdomen)
• Clitoral enlargement
• Cessation of menses (typically within 2–6 months)

It also suppresses ovarian function and endogenous estrogen production.

GnRH agonists such as leuprolide and goserelin work differently. They suppress the body's own sex hormone production by downregulating the pituitary gland after an initial stimulation phase. These drugs may be used alongside testosterone to more fully suppress estrogen, or they may be used alone in transgender and nonbinary youth to delay puberty, giving adolescents more time before irreversible pubertal changes occur.

Common Side Effects and Drug Interactions

Testosterone therapy carries several side effects that nurses should monitor for:

• Dermatologic: Acne, oily skin, male pattern baldness (androgenic alopecia)
• Metabolic: Weight gain, increased red blood cell production (polycythemia), unfavorable changes in lipid profile
• Cardiovascular: Elevated blood pressure, increased cardiovascular disease risk
• Behavioral/other: Mood changes (irritability, aggression), increased libido, sleep apnea

Polycythemia deserves special attention. Testosterone stimulates erythropoiesis, and an elevated hematocrit (generally above 50–54%) increases the risk of thromboembolic events like stroke or deep vein thrombosis. This is one of the most important lab values to track.

Drug interactions to know:

• Anticoagulants (e.g., warfarin): Testosterone can enhance anticoagulant effects, increasing bleeding risk. Monitor INR closely.
• Insulin and oral hypoglycemics: Testosterone can alter glucose metabolism, potentially decreasing the effectiveness of these drugs. Blood glucose levels may need more frequent monitoring.
• Corticosteroids: Concurrent use may worsen fluid retention and edema.

Essential Nursing Considerations

Before starting therapy:

1. Obtain a thorough medical history, including cardiovascular risk factors, mental health history, and any history of thromboembolic events.
2. Perform a baseline physical examination.
3. Order baseline labs: complete blood count (CBC) with hematocrit, lipid panel, fasting glucose or $\text{HbA1c}$, and liver function tests (LFTs).

Ongoing monitoring during therapy:

1. Check hematocrit and hemoglobin at 3 months, 6 months, then every 6–12 months. If hematocrit rises above 50–54%, the dose may need to be reduced or therapy temporarily held.
2. Monitor blood pressure and lipid profile regularly to assess cardiovascular risk.
3. Assess for signs of sleep apnea (snoring, daytime fatigue, morning headaches) at each visit.
4. Repeat LFTs periodically, especially with oral formulations (though oral testosterone is rarely used in gender-affirming care).

For administration:

• Use proper IM injection technique (typically the vastus lateralis or ventrogluteal site) to minimize pain and complications such as oil embolism or injection site reactions.
• If the client will self-inject, teach and have them return-demonstrate the technique, including site rotation, aseptic technique, and proper needle disposal.

Collaborate with mental health professionals to provide comprehensive, whole-person care. Maintain a nonjudgmental and affirming approach throughout all interactions.

Important Client Education Points

Timeline of changes: Physical changes happen gradually. Voice deepening and body hair growth may take 6–12 months to become noticeable, and full effects can take 2–5 years. Setting realistic expectations early helps prevent frustration.

Recognizing complications: Teach clients to watch for and report:

• Symptoms of polycythemia: headaches, dizziness, flushing, visual changes
• Signs of sleep apnea: excessive daytime sleepiness, loud snoring, waking with gasping
• Chest pain, sudden shortness of breath, or leg swelling (possible thromboembolic event)

Fertility considerations: Testosterone suppresses ovulation and can significantly reduce fertility, but it is not a reliable contraceptive. Clients who may want biological children in the future should be counseled about fertility preservation options (such as oocyte or embryo cryopreservation) before starting therapy.

Consistency matters: Masculinizing effects depend on continued testosterone use. Stopping therapy will lead to partial reversal of some changes (e.g., fat redistribution, menses may return), though other changes like voice deepening and clitoral enlargement are generally permanent.

Healthy lifestyle: Encourage a balanced diet, regular exercise, and stress management. These support cardiovascular health, which is especially relevant given testosterone's effects on lipids and blood pressure.

Support resources: Connect clients with support groups and LGBTQ+ organizations. Emotional support and community connection are valuable parts of comprehensive care during transition.