What is the best course of action for a man with no libido (sex drive) or desire, potentially due to hormonal imbalances, underlying medical conditions, or medication side effects, such as selective serotonin reuptake inhibitors (SSRIs)?

Evaluation and Management of Male Hypoactive Sexual Desire

Begin with a comprehensive medical and psychosexual history, followed by targeted laboratory testing including morning total testosterone (on two separate occasions), and assess for reversible causes including medications (particularly SSRIs and beta-blockers), depression, relationship issues, and underlying medical conditions before initiating treatment. 1

Initial Diagnostic Workup

The evaluation must systematically identify reversible causes:

• Obtain morning total testosterone levels on at least two separate occasions to confirm any abnormality, as this is the foundation of hormonal assessment 2
• If total testosterone is normal but clinical suspicion remains, measure free testosterone by equilibrium dialysis and sex hormone-binding globulin (SHBG), particularly in obese men where low SHBG can mask truly low free testosterone 2
• Check serum prolactin if testosterone is low or low-normal with concurrent low/normal LH levels to rule out hyperprolactinemia 2
• Measure LH and FSH if testosterone is confirmed low to distinguish primary from secondary hypogonadism 2

Medication Review and Reversible Causes

SSRIs, beta-blockers, narcotics, and hormonal therapies are the most common medication-related causes of reduced libido and must be identified early. 1

• Depression, anxiety, diabetes, hypertension, and cardiovascular disease are strongly associated with reduced libido 1
• Relationship distress, communication issues, and partner sexual dysfunction frequently contribute to or exacerbate low desire 3, 4
• Use validated screening tools such as the International Index of Erectile Function (IIEF) which covers sexual desire as one of five domains 1

Treatment Algorithm Based on Testosterone Status

If Testosterone is Low (<300 ng/dL on two occasions):

Testosterone replacement therapy is indicated only when morning free testosterone is frankly low on at least two separate assessments and after completing the hypogonadism workup. 2, 5

• For men desiring fertility: first-line treatment is gonadotropin therapy with hCG initially, followed by FSH addition after testosterone normalization 2
• For men not concerned with fertility: testosterone replacement improves libido, erectile function response to PDE5 inhibitors, and metabolic parameters 2, 5
• Transdermal preparations provide stable day-to-day testosterone levels, while intramuscular injections avoid daily administration but cause fluctuating levels 2

If Testosterone is Normal:

Primary reduced libido (without hypogonadism, hyperprolactinemia, or psychopathology) requires a different approach focused on psychological and relationship factors. 3, 4

• Cognitive behavioral therapy has demonstrated effectiveness for improving sexual functioning in men with low libido 4
• Sexual health counseling and couples therapy should address relationship distress and communication issues 4, 6
• Testosterone supplementation is NOT beneficial for men with normal total testosterone levels 7

Management of SSRI-Induced Sexual Dysfunction

If low libido is secondary to SSRI use, adding a phosphodiesterase-5 inhibitor (sildenafil 50-100mg as needed, or tadalafil 10-20mg as needed or 5mg daily) is the recommended first-line adjunctive therapy. 8

• PDE5 inhibitors improve not just erectile function but also orgasmic intensity and overall sexual satisfaction in men on antidepressants 8
• Ensure patients are not taking nitrates (absolute contraindication) and can perform moderate physical activity before starting PDE5 inhibitors 8
• Trial at least 5-8 separate occasions at maximum dose before declaring treatment failure 8
• Monitor depression symptoms closely when making medication changes 8

Treatment of Concurrent Erectile Dysfunction

If reduced libido is secondary to erectile dysfunction, treat the ED first or concomitantly, as this often improves desire. 1

• Four EMA-approved PDE5 inhibitors (sildenafil, tadalafil, vardenafil, avanafil) are first-line pharmacotherapy for erectile dysfunction 1
• Cardiovascular risk assessment is warranted, as erectile dysfunction identifies increased cardiovascular disease risk 2

Common Pitfalls to Avoid

• Do not prescribe testosterone supplementation without confirming low testosterone on two separate morning measurements 2, 7
• Do not ignore medication side effects, particularly SSRIs, beta-blockers, and narcotics, which are frequently overlooked causes 1
• Do not fail to assess relationship and psychological factors, as chronic frustration of fundamental psychosocial needs for acceptance, closeness, and security is a critical but often neglected factor 6
• Do not perform routine laboratory tests beyond testosterone, prolactin, LH, and FSH unless directed by specific findings from history or physical examination 1

Lifestyle Modifications

Implement lifestyle modifications regardless of testosterone status, as weight loss, increased physical activity, smoking cessation, and limiting alcohol consumption can improve sexual function. 2, 4