Based on PubMed | Can melanoma treatments, such as immunotherapy or targeted therapy, cause low libido, and how can this side effect be managed?

Low libido can occur with melanoma treatments, including both immunotherapy and targeted therapies, and it often has multiple, overlapping causes such as treatment side effects, hormone changes, fatigue, mood shifts, and stress. ^{[1] [2]} Targeted therapies (BRAF/MEK inhibitors) also commonly acknowledge a reduced desire for sex during treatment, and emotional factors can compound this effect. ^{[3] [4] [5] [6]}

Why libido can drop during treatment

• Immune checkpoint inhibitors (like ipilimumab, nivolumab) can inflame hormone‑producing glands, leading to endocrine problems such as hypophysitis (pituitary inflammation), thyroid dysfunction, and adrenal insufficiency that may lower sex hormones and reduce sex drive. ^{[7] [8]}
• With ipilimumab plus nivolumab, adrenal insufficiency has been reported in a notable minority of recipients, which can cause fatigue, weakness, and decreased libido unless treated. ^[9]
• These endocrine effects can be serious if unrecognized but are manageable with prompt evaluation and hormone replacement when needed. ^{[7] [8]}
• Patient information for immune therapy lists decreased sex drive among possible mood and behavior changes, highlighting that both physical and emotional pathways contribute. ^{[1] [2]}
• Targeted therapy combinations and single agents (e.g., vemurafenib, cobimetinib, encorafenib/binimetinib, dabrafenib/trametinib) commonly note a potential decrease in sexual desire related to the treatment or its side effects. ^{[4] [3] [5] [6]}

Red flags that warrant urgent medical review

• New or worsening headaches, dizziness or fainting, profound fatigue, confusion, or lower back/leg pain can signal adrenal or pituitary problems during immunotherapy and should prompt immediate contact with the care team or emergency evaluation. ^{[1] [2]}
• Other hormone‑related symptoms to report include feeling unusually hot or cold, excessive sweating, heart rhythm changes, and unexplained weight changes. ^[10]

How doctors evaluate the cause

• Clinicians typically consider both general side effects (fatigue, pain, nausea, sleep changes) and specific endocrine problems that may suppress testosterone or estrogen. ^[11]
• When endocrine effects are suspected, tests may include pituitary, thyroid, and adrenal panels (for example, morning cortisol, ACTH, TSH, free T4, LH/FSH, prolactin, and sex hormones), because hypophysitis and adrenal insufficiency are recognized immune therapy toxicities. ^{[12] [9]}
• Identifying and treating hormone deficiencies early can be crucial, since some pituitary injury may be long‑lasting and require ongoing replacement. ^[7]

Practical management strategies

• Treat the underlying cause: If endocrine dysfunction is found (e.g., secondary adrenal insufficiency or pituitary hormone deficits), appropriate hormone replacement and ongoing monitoring are generally recommended and can improve energy, mood, and sexual interest. ^{[7] [9]}
• Manage general contributors: Address fatigue, pain, sleep, and mood, as these commonly lower desire irrespective of hormone status. ^[11]
• Sexual function tools and therapies:
  • For erection problems, medications such as phosphodiesterase‑5 inhibitors, vacuum devices, injections, and stepwise “erectile rehabilitation” approaches can help, ideally with guidance from sexual medicine clinicians. ^[13]
  • For vaginal dryness or discomfort, vaginal moisturizers and lubricants are often useful, and individualized pelvic health strategies can be added as needed. ^[14]
  • Counseling individual or couples can reduce anxiety, improve communication, and support sexual well‑being during and after treatment. ^[15]
• Build a supportive care plan: Comprehensive sexual health programs commonly combine medical treatments (including hormone replacement when appropriate), symptom control, and counseling to tailor care to individual needs and goals. ^[16]

What to discuss with your oncology team

• Tell your team about low libido, erectile issues, vaginal dryness, or pain, and any symptoms that might suggest hormonal problems. ^[1]
• Ask whether your current regimen is associated with endocrine side effects and whether routine hormone testing is needed based on your symptoms. ^[8]
• Discuss evidence‑based options for sexual function support, such as medications, lubricants, devices, pelvic therapy, and referrals to sexual medicine specialists. ^{[14] [15]}

Quick reference: therapies and libido

Treatment type	Can it lower libido?	Typical mechanisms or notes
Immune checkpoint inhibitors (e.g., ipilimumab, nivolumab, or in combination)	Yes, in some people	Mood/behavior changes including decreased sex drive are noted; endocrine irAEs (hypophysitis, adrenal insufficiency, thyroid disease) can reduce sex hormones and energy. [1] [2] [7] [9]
Targeted therapy (BRAF/MEK inhibitors such as dabrafenib/trametinib, vemurafenib, encorafenib/binimetinib, cobimetinib/vemurafenib)	Yes, reported in patient materials	Decreased desire often linked to treatment side effects and emotional impact. [6] [4] [5] [3]

Key takeaways

• Decreased libido is a recognized possibility with both immunotherapy and targeted therapy for melanoma, often tied to side effects, emotional stress, and sometimes hormone disturbances. ^{[1] [4]}
• Immune‑related endocrine issues like hypophysitis and adrenal insufficiency are particularly important to detect early because targeted hormone therapy can be highly effective. ^{[7] [9]}
• A combined approach medical evaluation for reversible causes, symptom control, sexual function treatments, and supportive counseling usually provides the best results. ^{[13] [14] [15]}