Low Testosterone: Symptoms, Causes, Diagnosis, Treatment, Complications, Prognosis and Prevention

Also called low T, it is a term used by doctors to describe an abnormal hormone testosterone level.

When properly measured, low testosterone is considered below 300 ng/dl in male patients, although some clinicians suggest that the normal range is 270-1070 ng/dl.

Other terms for low T include hypogonadism (primary, secondary, and tertiary, depending on the cause of the low T) and testosterone deficiency (TD).

Testosterone is a steroid hormone produced in the adrenal glands of both sexes and the testes of men’s and women’s ovaries.

Testosterone is mainly responsible for the formation and maintenance of male sexual characteristics, including the increased bone and muscle development seen in men.

Testosterone levels in humans are regulated by hormones released from the brain; In men, the hypothalamus and pituitary glands in the brain increase testosterone during puberty, and male characteristics develop (e.g., penis enlargement, facial hair, interest in sex).

Although most low testosterone problems center on adult men, low T is not limited to adult men. However, the definition and characterization of low T in women are less clear than in adult men.


Testosterone production is part of the body’s endocrine system.

What Causes Low Testosterone?

The causes of low T are many and can be separated into three categories: primary, secondary, and tertiary.

The primary types of primary or low T hypogonadism refer to injury or failure of the organs that are the leading producers of testosterone, the testes, and ovaries.

Causes of primary low T include:

  • Scrotal or injured testicles.
  • Undescended testicles.
  • Mumps.
  • Orchitis.
  • Chemotherapy.
  • Chromosomal abnormalities.
  • Ovarian failure or surgical removal.
  • Aging.

The causes of secondary low-T or secondary hypogonadism are related to the regulation of testosterone in the pituitary gland.

On the other hand, tertiary low T or tertiary hypogonadism is related to the regulation of testosterone in the hypothalamus (a gland of the brain that regulates the pituitary gland and other glands).

Most causes of secondary and tertiary low T are the same for the pituitary and hypothalamus; Furthermore, the reasons can affect both simultaneously.

The causes of low and secondary – secondary and tertiary include:

  • Tumors are associated with the pituitary or hypothalamus.
  • Chemotherapy of nearby tumors.
  • Gland malformations.
  • Decreased blood flow to the glands for any reason.
  • Inflammation of the gland due to disease (HIV, tuberculosis, sarcoidosis).
  • Taking anabolic steroids improves performance or muscle mass (athletes, bodybuilders).

Other causes of low testosterone don’t fit well into the categories above. Most notably, obesity, in which fat cells increase the conversion of testosterone to estrogen.

Diseases such as diabetes, kidney disease, COPD, high blood pressure, and lifestyles that include smoking and drug abuse also contribute to low T.

Other less common causes include modified cellular receptors for testosterone and unusual cellular mechanisms rarely identified.

What are the symptoms?

There are many signs and symptoms of low T. The most common sign and symptom that men take to their doctors is erectile dysfunction (no or no erection of the penis).

However, many other signs and symptoms can also occur:

  • Reduction of sexual desire.
  • Reduced or absent orgasm.
  • Reduced or absent spontaneous erections.
  • Loss or removal of the pubic, armpit, or facial hair.
  • Depression .
  • Removal of the size of the testicles.
  • Breast discomfort or enlargement.
  • Hot flashes or sweating
  • Reduction of force.
  • Sleep disorders.
  • Memory reduction.

Other signs can be seen on examination or tests performed by a doctor:

  • Anemia (decrease in red blood cells).
  • Osteoporosis.
  • Reduced or absent sperm production; sterility.
  • Increase in body fat (body mass index).
  • Many of the above can be seen in women with low T, except for male-specific symptoms.

When should a person seek medical attention for low testosterone?

A person should seek medical attention if they notice any of the symptoms (as explained above) that are associated with low T.

Men with erectile dysfunction should seek medical attention and not rely on medications or cures advertised on television, the Internet, or elsewhere to self-diagnose the problem.

Women who have symptoms should discuss them with their OB / GYN or endocrinologist.

How is it diagnosed?

Low T is presumptively diagnosed by the person’s history of signs and symptoms (see symptoms of low T above) and physical examination.

For men, there is a blood test that can detect testosterone levels and provides the basis for a definitive diagnosis of low T. Normal values ​​range from 270 to 1070 ng/dl, but the definition of ‘normal’ varies slightly depending on the different experts.

Most blood test measurements are done in the morning because this is when men’s daily testosterone production is highest.

Blood tests for women are more variable in results (some researchers suggest that women have about one-third to one-eighth the male testosterone level), so the diagnosis is more complex and is often based on symptoms and physical findings.

Other tests (blood, imaging) may be performed to diagnose whether the low T has secondary or tertiary causes or whether underlying conditions contribute to the development of symptoms or inhibit testosterone production.

What is the treatment for low testosterone?

In men, treatment for low T is based on two approaches.

If there are underlying causes of low T (e.g., HIV, tumors, chemotherapy, diabetes, obesity), the doctor should begin individualized treatment for these underlying causes.

Low T levels can be supplemented with hormones prescribed by a doctor. Expert recommendations vary when dealing with hormones; some suggest treatment if the levels are 300 ng/dl, while others recommend starting treatment if the stories are 230 ng/dl.

Although researchers suggest that approximately 70% of men age 70 and older have low T, some researchers suggest that hormone treatment may not be effective in this age group.

However, when prescribed, hormone therapy (testosterone) can be given in an injection, granule implant, in a skin patch, in a gel placed on the skin, or as an oral gel or putty applied to the gums.

There is no approved method for testosterone replacement in women. However, some doctors may still prescribe some form of testosterone for women, but the efficacy and safety of this treatment have not been proven.

The use of topical hormones should be done with care. Women should not contact the area of ​​skin treated with resorbable testosterone, as the hormone can also be absorbed through the skin.

This could cause women to develop masculine characteristics.

What are the complications?

The complications of low T vary between individuals. For adult men, the most common symptom of erectile dysfunction can lead to stress, depression or marital discord, and intense sexual desire, except for erectile dysfunction of the penis; Similar complications can occur in women.

Additionally, muscle mass, bone density, and fertility can be reduced.

Recent studies suggest a link between testosterone therapy and an increased risk of heart disease.

For example, a 2014 study reported that testosterone therapy could increase the risk of a heart attack in men 65 and older and in younger men who have a history of heart disease. The use of testosterone should be discussed with your doctor.

What is the prognosis for a person with low testosterone levels?

In adult men, the prognosis for a patient with low T can range from good to fair, depending on the person’s response to treatment and their age (older patients may not respond as well to treatment).

Those patients diagnosed and treated late in the disease process may suffer from muscle wasting and osteoporosis.

The prognosis for women is less clear; testosterone treatments will depend on experimental or unapproved protocols designed individually for each woman and her physician (s).

How is low testosterone prevented?

Low T caused by genetic factors cannot be prevented, nor can low T be discouraged if the underlying cause is a disease caused by inherited genetic factors or by necessary treatments, such as chemotherapy.

However, some causes that can result in low T, such as obesity, smoking, and drug abuse, can be avoided by changing a person’s lifestyle.

These changes can prevent or delay the onset of low T. Early diagnosis and treatment can prevent loss of muscle and bone mass.