Low Libido

Also known as:

  • sexual dysfunction
  • low sexual desire
  • poor sexual arousal
  • sexual disorder
  • lack of sex drive
  • hypoactive sexual desire disorder (HSDD)

Libido is often defined as sexual desire, some never feel the desire for sex, whilst some have strong desires and enjoy it.

Low libido affects both men and women and are affected by many factors like your mood, interpersonal functioning and psychotropic medications.  

Not only psychotropic drugs, but corticosteroids (steroid hormones) can affect sexual behaviour.  Studies show that giving pregnant women carrying a male child these drugs during the last trimester, lowers dopamine and testosterone in adulthood and affects loss of sexual function.

In women, sexual dysfunction can lead to:

  • delayed vaginal engorgement
  • diminished vaginal lubrication
  • pain or discomfort with intercourse
  • lowered vaginal sensation and/or orgasm
  • diminished clitoral sensation and/or orgasm

Low libido in women does not prevent orgasms.

Low libidos are experienced by many women after giving birth as well as painful intercourse, vaginal dryness, perineal pain and reduced frequency of orgasm.

In men, sexual dysfunction can lead to reduced smooth muscle function, which leads to impaired flow of blood to the corpora, impaired synthesis and release of endothelial nitric oxide and a failure to the veno-occlusive mechanism, all leading to erectile dysfunction or impotence and low libido.


Physical causes:

  • low dopamine
  • low progesterone
  • low vitamin D3
  • low testosterone 
  • low zinc
  • hyperlipidaemia (abnormal elevated levels of lipids)
  • atherosclerosis (vascular disease or ASVD) 
  • hypothyroidism
  • alcoholism
  • drug abuse
  • diabetes
  • CVD (diseases involving the heart and blood vessels)
  • drugs such as - tranquillisers, antidepressants, antihypertensives
  • hair loss remedies
  • hyperprolactinaemia (abnormally high levels of prolactin in the blood)
  • hypertension
  • obesity

Psychological causes:

  • depression
  • postnatal depression
  • stress
  • anxiety
  • childhood trauma
  • previous sexual abuse or rape

Many hormones, neurotransmitters and neuropeptides are involved in the control of sexual behaviour.  Some include:

  • progesterone
  • dopamine
  • nitric oxide (NO)
  • acetylcholine
  • adrenocorticotropin/alpha-melanocyte stimulation hormone
  • testosterone
  • oxytocin
  • prolactin
  • serotonin
  • opioid peptides

All helpful in sexual behaviour except for prolactin, serotonin and the opioids, which inhibit sexual performance leading to low libido.

Without looking at the side effects Testosterone, (also known as 'the' libido increasing agent in both men and women) has, it is often prescribed, believing that TRT (testosterone replacement therapy) is the answer!

Side effects of testosterone treatment in women

  • hirsutism (excessive hair)
  • scalp hair loss
  • oily skin and hair
  • deepened voice
  • enlarged clitoris
  • insulin resistance - metabolic syndrome and cardiovascular disease
  • increased visceral fat
  • cancer
  • advanced increase in glycation end-products (AGE's)

Side effects of testosterone treatment in men

  • gynaecomastia (enlarged breast tissue)
  • reduction in sperm
  • increased estradiol levels
  • decreased HDL levels
  • increased manic symptoms
  • rise in DHT
  • hair loss

Alarmingly, a 200mg per week testosterone injection is given as a contraceptive, to reduce sperm and 5 to 10mg per day is used by men when using a testosterone gel called Androgel or similar.

Some untruths/lacking evidence

  • reduction in sperm does not cause low libido
  • low sexual desire and sexual dysfunction are associated with low blood testosterone levels in women

Menopause - it is a known fact that a decline in sexual function occurs at menopause.  However, there is no significant decline in circulation testosterone levels.  A total hysterectomy reduces testosterone levels and some women can benefit from TRT but other hormones are needed too. 

Evidence shows that progesterone plays a far greater role in sexual health in both men and women.  It was confirmed in the 1960's and again in the 1980's that there is a surge of progesterone about 50 hours before ovulation, this surge comes from the brain.  This surge was later learned to be essential for the facilitation of feminine sexual behaviour.

Studies failed to look at the key role that progesterone, wrongly thought of as a female hormone, has on low libido in a male, and how it affects his sexual activities.

Progesterone is produced in:

  • ovaries
  • testes
  • adrenal glands
  • brain and glial cells
  • placenta in pregnant females

And they say it is primarily a female hormone ..... wrong!  It is not a sex hormone and it plays no part in the secondary sexual characteristics which takes place at puberty.  It is the precursor to the sex hormones estrogen and testosterone as well as cortisol and aldosterone.

In men progesterone influences spermiogenesis, sperm capacitation/acrosome reaction and testosterone biosynthesis in the Leydig cells (these are found adjacent to the seminiferous tubules in the testicle.

A study found that in men there is a strong correlation between testosterone, progesterone and cortisol, but in women, progesterone was positively correlated with testosterone and cortisol, but testosterone and cortisol were uncorrelated.

There is also evidence that dopamine plays a significant role.  Progesterone receptors (PR) act as transcriptional mediators for dopamine, as well as progesterone.   What this means, is that PR's are needed by dopamine to induce sexual behaviour in both male and female mice.

Premature ejaculation is the most common male sexual dysfunction.  Dopamine not only facilitates male sexual behaviour including:

  • sexual motivation
  • arousal
  • penile erection

It also controls ejaculation!

  • Parkinson's disease - where the dopamine pathway has become dysfunctional, the use of dopamine agonists by young men leads to hypersexuality.
  • Injections of adrenocorticotropin (ACTH) and melanocyte stimulating hormone (MSH) - into the hypothalamic periventricular region of the brain causes penile erection.
  • Cocaine - extremely popular, is a potent nervous system stimulant which enhances erections by raising dopamine due to blocking it's re-uptake.
  • Serotonin - restrains sexual behaviour which explains why SSRI's impair erection, ejaculation and libido.

Hyperprolactinemia is usually treated with drugs which mimic dopamine's action, the most common are cabergline and dromocriptine.  High dopamine inhibits prolactin. Tyrosine, an amino acid, is the precursor to dopamine.  Hyperprolactinemia takes place naturally after sexual activities, however, elevated prolactin levels  cause sexual dysfunction, leading to hyprogonadism, impotence and low libido.  High prolactin suppresses dopamine production.  It can be caused by drugs, kidney failure, hypothyroidism, and by prolactinoma (a brain tumour secreting excess prolactin).

Tyrosine - is essential for any stressful situation:

  • cold
  • fatigue
  • emotional trauma
  • prolonged work
  • sleep deprivation

It improves memory, cognition and physical performance.  A protein deficiency and stress lowers tyrosine levels, which reduces dopamine. Prolactin levels rise if dopamine levels drop.  Dopamine is essential for a normal sexual response, increased prolactin causes a drop in libido!  A vitamin D3 deficiency inhibits tyrosine dyfroxylase resulting in a disturbance in the dopamine pathway.

Also important for a normal sexual function are:

  • nitric oxide (NO)
  • hydrogen sulfide (H(2)S)
  • sodium hydrosulfide (NaHS)

They all have significant vasodilatory and smooth muscle relaxant effects in both males and females. Progesterone also has the same relaxant properties.  

Erectile Dysfunction (ED) could indicate cardiovascular disease.  Before any drug is taken, risk factors for CVD should be checked first and corrected. Usually ED will cease once corrected.  These include:

  • diabetes
  • hypertension
  • arterial calcification 
  • inflammation in the vascular endothelium

An erection, as with the engorgement of the vagina in women, relies on a good supply of blood. If CVD is present this will be severely diminished.

A lack of VITAMIN D3 has been found to lead to CVD and diabetes.  If deficient in vitamin D3 it can cause the renin-angiotensin-aldosterone system to react, raising blood pressure.  Calcified arteries are associated with low vitamin D3, so is inflammation.

Calcified arteries are also caused by low levels of vitamin K2 and magnesium.  Both are important co-factors to vitamin D3, ensuring deposition of calcium in bones and preventing deposits in arterial plaque.  Excessive free calcium in the blood causes calcified arteries and heart disease.

A lack of vitamin D3 reduces the benefits of progesterone and is needed for the conversion of the amino acids tyrosine and dopamine.

Excess blood glucose, as found in diabetes and occasionally in Insulin Resistance, reduces nitric oxide levels, preventing blood from entering and remaining in the corpora cavernosa to cause an erection.  Inositol together with folic acid has been found to reverse the effects of high blood glucose, thereby preventing and treating ED.

Studies have found that after child birth, and entering Menopause women experience low libido.  Progesterone levels can drop sharply after birth causing not only low libido, but depression too.  Levels of progesterone drop during Peri-Menopause, whereas estrogen and testosterone remain at normal levels.  Low libido is one of many adverse symptoms women may experience during peri-menopause. 

Natural Treatment of Low Libido

Studies show that progesterone is essential for a normal sexual response.

Progesterone - women should use 100mg/3ml to 200mg/6ml per day depending on symptoms and how severe they are.  Men should use 100mg to 100mg per day, again depending on symptoms.  For more information see How to use Progesterone Cream.

It is vital that you read Estrogen Dominance when using progesterone for the first time.

Vitamin D3 - is vital.  it is connected to every single cell in our bodies and is required to help our cells function properly.  It is a potent antioxidant and a lack of it leads to a disturbance in the dopamine pathway.  It is essential in stimulating the enzyme tyrosine hydroxylase which converts tyrosine into dopamine.  A Vitamin D3 deficiency reduces the benefits of progesterone and raises levels of testosterone.  It is much safer to take vitamin D than TRT.

Dopamine - appears to be needed for a normal sexual response.  The amino acid tyrosine is the precursor to dopamine.  Low dopamine causes prolactin to rise, tyrosine can prevent this.  Progesterone suppresses prolactin levels.

Nitric Oxide (NO) - is a strong vasodilator and is essential for penile erections and vaginal engorgement.  The precursor to NO is arginine, also a strong antioxidant.  Progesterone and vitamin D3 stimulate NO products.  Progesterone is also a strong vasodilator.

Hydrogen Sulfide (H(2)S) and Sodium Hydrosulfide (NaHS) - also vasodilators.  The precursor to the amino acid N-Acetyl Cysteine (NAC) which is an extremely powerful antioxidant.

Inositol/Folic Acid - controls high blood glucose.

If you suffer from Low Libido, please consider taking the above.  Have your prolactin, progesterone and vitamin D levels tested.

For more information on Vitamin D3 levels, test kits etc, see the following:

See Hormone Testing to see what your hormone levels should be.

Low Libido References

Vitamin D and Erectile Dysfunction

Drugs & Medications for erectile dysfunction 



Netdoctor lack of sex drive in women

Netdoctor lack of sex drive in men

Erectile Dysfunction