From the Guidelines
A comprehensive workup for low libido in a male taking finasteride should begin with a detailed medical history and physical examination, including assessment of the temporal relationship between finasteride initiation and libido changes, as this medication is known to cause sexual dysfunction in 2-5% of users through its inhibition of 5-alpha reductase and subsequent reduction in DHT levels 1.
Initial Evaluation
The initial evaluation should include:
- Laboratory testing: morning total testosterone, free testosterone, estradiol, prolactin, thyroid function tests (TSH, free T4), comprehensive metabolic panel, and complete blood count.
- Measurement of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) to evaluate the hypothalamic-pituitary-gonadal axis.
- Discussion of the possibility of discontinuing finasteride if appropriate, as sexual side effects may resolve within weeks to months after cessation.
Modifiable Factors
Address modifiable factors that may contribute to low libido, including:
- Stress
- Sleep disturbances
- Relationship issues
- Depression
- Anxiety
- Medication review, as many drugs (antidepressants, antihypertensives, opioids) can impact sexual function.
Testosterone Replacement Therapy
If testosterone levels are low, testosterone replacement therapy may be considered after appropriate screening, as it may relieve symptoms of ED, problems with ejaculation, or problems with orgasm for survivors with hypogonadism 1.
Referral to Specialists
For persistent symptoms despite these interventions, referral to endocrinology, urology, or sexual health specialists may be warranted for further evaluation and management.
Additional Considerations
Additional considerations include:
- Risk factor modification, such as smoking cessation, weight loss, increasing physical activity, and avoiding excess alcohol consumption.
- Treatment of psychosocial problems, with referral to sex and couples therapy as appropriate.
- Pelvic physical therapy (ie, pelvic floor muscle training) may improve sexual function in this population.
- Vibratory therapy may reduce problems with premature ejaculation.
From the FDA Drug Label
- sexual dysfunction that continued after discontinuation of treatment, including erectile dysfunction, decreased libido and ejaculation disorders (e. g. reduced ejaculate volume).
- In a separate study in healthy men treated with finasteride 1 mg per day (n=82) or placebo (n=69), mean circulating levels of testosterone and estradiol were increased by approximately 15% as compared to baseline, but these remained within the physiologic range
- However, impotence and decreased libido may occur in patients treated with finasteride tablets [see Adverse Reactions (6. 1)].
The work up for low libido in a male on finasteride should consider the potential effects of finasteride on sexual function, including decreased libido.
- Hormone levels: Check testosterone and estradiol levels to assess if they are within the physiologic range.
- Discontinuation of treatment: Consider discontinuing finasteride to see if libido improves, as sexual dysfunction has been reported to continue after discontinuation of treatment in some cases 2.
- Alternative treatments: Explore alternative treatments for the underlying condition being treated with finasteride, such as benign prostatic hyperplasia (BPH).
- Monitor for other symptoms: Monitor for other symptoms such as erectile dysfunction and ejaculation disorders, which have been reported in patients treated with finasteride 2, 2.
From the Research
Workup for Low Libido in a Male on Finasteride
- The patient's symptoms of low libido while on finasteride should be evaluated in the context of potential sexual side effects associated with the medication 3, 4, 5.
- A thorough medical history and physical examination should be performed to rule out other potential causes of low libido, such as hypogonadism, erectile dysfunction, or other medical conditions 6, 7.
- The patient's finasteride dosage and duration of treatment should be assessed, as well as any other medications that may be contributing to low libido 3, 4.
- Laboratory tests, such as testosterone levels, may be ordered to evaluate for hypogonadism or other hormonal imbalances 6, 7.
- A discussion with the patient about the potential risks and benefits of continuing finasteride treatment, as well as alternative treatment options, should be undertaken 3, 4, 5.
Potential Treatment Options
- Discontinuation of finasteride may be considered, especially if the patient's low libido is suspected to be related to the medication 3, 4, 5.
- Testosterone replacement therapy (TRT) may be considered for patients with hypogonadism, as it has been shown to improve sexual function and libido in some men 6, 7.
- Other treatment options, such as counseling or lifestyle modifications, may also be recommended to address low libido and related sexual dysfunction 3, 4, 5.
Considerations for Management
- The nocebo effect, where patients experience adverse effects due to their expectations or anxiety about the medication, should be considered when managing finasteride-related sexual side effects 3.
- Patients should be informed about the potential risks and benefits of finasteride treatment, as well as alternative options, to make informed decisions about their care 3, 4, 5.
- Regular follow-up and monitoring of the patient's symptoms and treatment response should be performed to adjust the treatment plan as needed 6, 7.