Low Libido — Symptoms, Causes & Treatment | MyMedicPlus

Low libido, medically known as hypoactive sexual desire disorder (HSDD), is a persistent or recurrent deficiency in sexual desire causing personal distress. It is multifactorial, involving hormonal, psychological, relational, and medical factors. It affects 30-40% of women and 15-20% of men at some point in their lives. Hypoactive sexual desire disorder (HSDD) is formally defined as persistently deficient or absent sexual thoughts, fantasies, and desire for sexual activity, causing clinically significant personal distress or interpersonal difficulty — and not better explained by a non-sexual mental disorder, significant relationship distress, medication effects, or medical illness alone. The distress criterion distinguishes HSDD from normal variation in sexual desire, which fluctuates significantly over the life course. Low libido is the most common female sexual complaint, affecting 30-40% of women across the life span, with highest prevalence in postmenopausal women and women with chronic illness. In men, prevalence increases with age and is strongly associated with hypogonadism, depression, and chronic disease burden. Effective treatment requires comprehensive assessment identifying all contributing factors — hormonal, psychological, relational, and medical.

Hormonal factors include low testosterone, estrogen deficiency (menopause, postpartum), hypothyroidism, and hyperprolactinemia. Psychological causes include depression, anxiety, stress, body image issues, and relationship conflict. Medications causing low libido include SSRIs, antihypertensives, and opioids. Chronic illness and fatigue are also significant contributors. Specific hormonal mechanisms: testosterone is the primary hormone driving sexual desire in both sexes — testosterone acts on hypothalamic and limbic brain centres. In women, testosterone levels decline progressively through the reproductive years and further at menopause; postmenopausal women have 50% lower testosterone than premenopausal women. In men, testosterone declines approximately 1-2% annually from age 30. Hyperprolactinaemia — from a pituitary prolactinoma or dopamine-blocking medications — directly suppresses GnRH and testosterone synthesis, causing low libido as a prominent symptom alongside galactorrhoea and oligomenorrhoea. Oral contraceptives raise SHBG (sex hormone-binding globulin), reducing bioavailable free testosterone and causing low libido in approximately 15-30% of users. Relationship-level causes include desire discrepancy between partners, loss of novelty, unresolved conflict, poor communication, and sexual boredom.

Primary symptom is a persistent reduction in sexual thoughts, fantasies, and desire for sexual activity causing clinically significant personal distress or relationship difficulties. Associated symptoms include reduced arousal, vaginal dryness, erectile difficulties, and avoidance of intimacy. Mood changes and fatigue may co-exist. The spectrum of low libido includes: reduced frequency of sexual thoughts or fantasies; decreased interest in initiating sexual activity or responding to partner initiation; reduced or absent sexual daydreams; and little pleasure or reward from sexual experiences that do occur. Important associated symptoms include: reduced genital engorgement (arousal disorder), vaginal dryness and dyspareunia (pain with intercourse from oestrogen deficiency — suggesting genitourinary syndrome of menopause), and difficulty reaching orgasm (anorgasmia). Depressive symptoms (low mood, anhedonia, social withdrawal), fatigue, and irritability may coexist as both causes and consequences. Partner sexual dysfunction (erectile dysfunction, premature ejaculation) can contribute to the patient's low desire.

A detailed sexual and medical history is essential. Hormone panel including total and free testosterone, LH, FSH, prolactin, TSH, and estradiol helps identify endocrine causes. Female Sexual Function Index (FSFI) and Male Sexual Health Questionnaire (MSHQ) are validated screening tools. Exclude medication side effects. The Female Sexual Function Index (FSFI) — a 19-item validated questionnaire — quantifies desire, arousal, lubrication, orgasm, satisfaction, and pain domains; a total score below 26.55 suggests female sexual dysfunction. The Male Sexual Health Questionnaire (MSHQ) assesses similar domains in men. Key hormone investigations: total testosterone (morning fasting sample), SHBG (calculate free testosterone), LH and FSH (to distinguish primary from secondary hypogonadism), prolactin (exclude hyperprolactinaemia), TSH (hypothyroidism reduces libido), and in women — oestradiol and FSH for menopausal assessment. Medication review is essential — SSRIs, SNRIs, antipsychotics, oral contraceptives, finasteride, spironolactone, opioids, beta-blockers, and proton pump inhibitors all reduce libido.

Address underlying causes first: optimize hormones, treat depression or anxiety, review and adjust medications. Testosterone therapy is evidence-based for men with confirmed hypogonadism and for postmenopausal women (off-label). Flibanserin (Addyi) is FDA-approved for premenopausal women with HSDD. Psychotherapy, couples counseling, and sex therapy are effective for psychological causes. Testosterone therapy for women: systemic testosterone (transdermal gel or cream providing 300 mcg/day — physiological female replacement dose) is evidence-based for postmenopausal women with HSDD causing distress; the ISSWSH (International Society for the Study of Women's Sexual Health) Position Statement (2019) supports its use. Monitor testosterone levels at 6 weeks and thereafter to ensure physiological levels are not exceeded. Flibanserin (Addyi): 100 mg at bedtime — a non-hormonal 5-HT1A agonist/5-HT2A antagonist FDA-approved for premenopausal women with acquired generalised HSDD; modest effect size (0.5 more satisfying sexual events per month); black box warning for hypotension with alcohol. Bremelanotide (Vyleesi): 1.75 mg subcutaneous injection PRN — melanocortin receptor agonist FDA-approved for premenopausal women; effective within 45 minutes. Psychosexual therapy and mindfulness-based approaches are equally or more effective than pharmacotherapy for psychological-origin low libido.

Untreated low libido can cause significant psychological distress, reduced self-esteem, relationship conflict, and sexual dysfunction in a partner. It may be a symptom of underlying depression, hypogonadism, or thyroid disease that requires independent treatment. Avoidance of intimacy can lead to relationship breakdown. Untreated low libido causes sustained psychological harm — depression, anxiety, low self-esteem, and shame are common, particularly when the individual perceives their sexual desire as abnormal or inadequate. Relationship consequences are significant: a desire discrepancy between partners — where one partner has markedly higher desire — causes frustration, rejection, and resentment on both sides, leading to conflict, reduced intimacy (emotional and physical), and in severe cases, relationship dissolution or infidelity. Male partners of women with HSDD report their own sexual dysfunction (erectile dysfunction, reduced desire) as secondary consequences. The impact on self-identity — particularly for individuals who valued their sexuality as part of their identity before the onset of HSDD — can be profound. Low libido secondary to unrecognised hypogonadism, hypothyroidism, or hyperprolactinaemia means these conditions remain untreated and continue to cause their own systemic complications.

Maintain hormonal health through healthy lifestyle choices, regular exercise, adequate sleep, and stress management. Address mental health conditions proactively. Review medications with a healthcare provider if low libido is suspected as a side effect. Open communication with partner and relationship counseling are key components of management. Prevention and lifestyle management of low libido address the modifiable risk factors. Hormonal optimisation: monitor thyroid function and treat hypothyroidism promptly (levothyroxine restores libido in hypothyroid patients). Manage hyperprolactinaemia with cabergoline (dopamine agonist) or treatment of the underlying cause. Discuss medication-related libido reduction with prescribing clinicians — switching from an SSRI to bupropion (a dopamine and noradrenaline reuptake inhibitor with significantly lower sexual dysfunction rates) may resolve medication-induced HSDD. Maintain cardiovascular health through regular exercise — exercise increases testosterone and improves sexual satisfaction through improved body image, mood, and cardiovascular function. Protect sexual relationship quality through open communication, regular non-sexual physical intimacy (maintaining connection), varied sexual activities, and when appropriate — couples therapy before sexual dysfunction becomes entrenched.

See your GP or a relevant specialist if: sexual desire has significantly decreased from your personal baseline and this change has persisted for more than 3-6 months and is causing personal distress or relationship difficulties; low libido is accompanied by other symptoms suggesting hormonal or thyroid disorder (fatigue, weight change, mood changes, erectile difficulties, or menopausal symptoms in women); you believe a medication you have started (particularly SSRIs, antidepressants, beta-blockers, or oral contraceptives) is causing low libido — do not stop medication without medical advice but discuss alternatives; and if vaginal dryness or painful intercourse accompanies low libido in women (genito-urinary syndrome of menopause is highly treatable). Do not feel embarrassed to discuss sexual health concerns with your GP — sexual wellbeing is an important component of overall health and quality of life. Referral options include endocrinology for hormonal evaluation (testosterone, thyroid, prolactin), gynaecology for women with menopause or pelvic conditions, and psychosexual therapy or couples counselling for psychological and relationship factors. Blood tests your GP should consider: total testosterone, SHBG, LH, FSH, prolactin, TSH, and in women — oestradiol and FSH for menopausal status assessment.