Testosterone is the main sex hormone found in men. It is synthesized in the male testes, the female ovaries and the adrenal cortex. For medical purposes, testosterone is used to treat acquired or congenital hypogonadism. It is also very effective in the treatment of breast cancer in postmenopausal women.
This treatment was first used in 1938 and approved by the American FDA in 1939. Anabolic steroids which are substances that are derived from testosterone have been greatly misused over the past years but after their approval and standardisation, they are now used as controlled substances. Testosterone was approved in 1991 as a safe substance to use for treatment. The Unimed Pharmaceuticals developed a compounded testosterone cream ‘ Androgel’ that was approved by the FDA in the year 2000 for treating testosterone deficiency which often results in hypogonadism conditions and symptoms and also to treat several injuries related conditions e.g. burns and injuries from accidents.
The transdermal application of this treatment targets similar regions as the injection applications. The maximum absorption and assimilation is attained when testosterone is injected directly into the densely muscled parts of the body since they have a numerous number of capillaries that can effectively absorb the testosterone into the blood plasma.
Endogenous testosterone is produced in the male body to facilitate the development of all sexual characteristics in men. This occurs from the foetal development before birth throughout their lifetime. Androgens begin their developmental functions in the foetus but it is most active during puberty and adolescence. After puberty, it still plays an important role in adulthood through to old age. Women also secrete testosterone in their ovaries but in very minute quantities. The testosterone secreted in the adrenal cortex is also very less so it cannot maintain the male sexuality and male sexual characteristics.
Increased levels of testosterone in the plasma of the body facilitate a negative feedback to the gonadotropin-releasing hormones. This leads to a reduction in the synthesis of endogenous testosterone, the follicle stimulating hormones, and the luteinizing hormones. Testosterone also influences the formation of erythro-proteins, blood glucose and the balance of calcium in the body. Androgens are highly lipid soluble so they can easily get into the cells of targeted tissues. In the cells, testosterone is enzymatically converted into 5-alpha dihydrotestosterone, in this state, it can form weak bonds with cytosolic receptors. The complex steroid receptors initiate some cellular changes in the nucleus which activate the action of the androgens.
Typically, endogenous androgens stimulate the RNA polymerase which promotes the synthesis of proteins in the body. The produced proteins are responsible for the normal development of the male sexual characteristics in men. These include; the growth and maturation of the penis, scrotum, the seminal vesicles and the prostate. On the onset of puberty, androgens facilitate the increase in growth rates and development of muscles and the redistribution of fat in the body. It also facilitates the deepening of the voice, the growth of body hair and the development of beards. It activates and maintains spermatogenesis, the fusion of epiphyses and it facilitates the termination of growth. In cases where endogenous androgens are not available, exogenous androgens can be used to facilitate normal body growth and development in males.
Testosterone can be administered in a number of ways. You can use a subcutaneous injection to administer it intramuscularly, it can be applied to the skin as a solution, ointment or a topical gel. It can also be administered as an implant of a long lasting and acting pellet, via the transdermal system and through the buccal cavity/mouth.
In the body’s serum testosterone binds to proteins but it has a higher affinity for the sex hormone binding factor globulin. The affinity of testosterone for globulin varies throughout various stages in life. It has the highest affinity at puberty then it declines during adulthood and increases again later in the old age. It has a half-life of 10-100 minutes which depend on its levels and concentration in the blood plasma.
Testosterone is transported in the body by an inhibitor. It undergoes metabolism in the liver to produce various steroids. Its activity is presumed to depend on dihydrotestosterone(DHT) which is a metabolite that binds to cytosol receptor proteins. The metabolism of DHT takes place in the reproductive tissues. Intramuscular testosterone is excreted in the urine and a smaller percentage through the faeces.
The absorption of testosterone that is in gel or solution form in the skin occurs periodically and continuously for up to 24 hours. This indicates that when administered through the skin, it mimics the mechanism of a sustained release.
Testosterone propionate injections are principally used as a treatment for hypogonadism or testosterone deficiency. It is also used to facilitate development in confirmed adolescent cases with a condition of delayed puberty.
Children should never be exposed to or use testosterone treatments unless specifically specified and instructed by a qualified physician. Testosterone gels and solutions are highly inflammable so they should not be exposed to fire. Smoking of tobacco and cigarettes should also be avoided when using any of these formulations.
The use of testosterone is contraindicated in male patients with breast cancer or prostate cancer because it can stimulate the development of cancer cells. It should be used cautiously in patients with prostatic hypertrophy because it can lead to the worsening of its signs and symptoms.
Testosterone replacement therapy is contraindicated in elderly patients with old-age related andropause or hypogonadism. There is insufficient information to support the safety and the effects of this treatment on them.
Patients with hepatic dysfunctions and hepatic diseases should use testosterone with caution since it can increase the accumulation of drugs in the body since it inhibits the clearance of drugs in the system.
Testosterone gel is specifically designed for male use and it is contraindicated in women. It can lead to serious hormonal changes and imbalances and adverse changes in their physiological characteristics and processes.
The use of this treatment is contraindicated in pregnant women, women who are trying to get pregnant and lactating or breastfeeding women because there is a very high probability that this medication can have irreversible adverse effects on a foetus and infants. Women on testosterone with a childbearing potential should, therefore, use an adequate and trusted method of contraception.
You should also avoid this medication if you have diabetes, lung disease, liver diseases, kidney diseases, hypersensitive reaction to testosterone and its products and other serious illnesses. Always inform your physician of all your medical conditions before you start taking this treatment.
Testosterone does not interact safely with a number of substances. it should not be used together with medicines that are used to treat diabetes, drugs used to prevent and treat blood clots e.g. propranolol and oxyphenbutazone. It should also not be used with other steroids like cortisone and prednisone.
It should not be used with goserelin or leuprolide because it can suppress the actions of this these substances in the body.
The use of an intranasal form of testosterone together with other nasally administered drugs is not advisable. The study of the effects of the interaction of these agents have not been established, but it is best to avoid them since they can cause adverse reactions.
The list above may not contain all possible interactions so you should inform your healthcare provider of all the other drugs that you are using. you should also indicate if you take alcohol, smoke or abuse some illegal drugs.
Male patients on testosterone therapy can experience feminization with prolonged treatment. This can be generally attributed to the conversion of androgens to oestrogens and the inhibition of gonadotropic hormone secretion.
The use of testosterone is associated with a libido increase or decrease. This occurs mostly as a result of an overdose. Priapism and a temporary erectile dysfunction can also be experienced.
The prolonged use of testosterone can lead to prostatic hypertrophy especially in the elderly males. Testosterone administration to female patients can cause an abnormal growth of facial hair, a reduced breast size, an enlarged clitoris, and deepening of the voice. If this treatment is discontinued, these symptoms may subside. A Prolonged treatment can lead to an irreversible development of masculine characteristics.
Topical and gel formulated testosterone products can cause irritation and reactions on the part of the skin where it is applied. Mild to moderate erythema can also be experienced.
An administration through the mouth or buccal cavity can lead to dental pains, gum tenderness, mouth and gum irritation, gum oedema and taste perversion.
Pharmaceutical doses of testosterone to prepubertal males and young males should be avoided. This can induce virilism which can be very dangerous because it is usually accompanied by an immature epiphyseal closure.
Testosterone treatments can lead to weight gain since testosterone facilitates the retention of sodium, potassium, chlorine, water and other inorganic substances which can lead to weight gain.
Animal studies have shown that testosterone can induce blood pressure and alter natriuresis which affects the renin angiotensin aldosterone systems and vasoconstriction of blood vessels.
It can cause hepatic dysfunctions so when on this treatment, you should monitor and test your liver periodically for normal functioning.
Intramuscular administration can lead to urticaria, post injection pains and furunculosis. Individuals receiving high doses of testosterone are at risk of polycythemia. Men receiving testosterone treatment for hypogonadism are also at risk of sleep apnea and its risk factors i.e. chronic lung diseases and obesity.
You should always contact your health service provider in case you experience any negative side effects and signs of allergic reactions.These may include but are not limited to; skin rashes, swelling of the lips, face and the tongue, chest tightness, headaches, passing out, dizziness and wheezing.
You should apply this medication every day at the same time to clean intact and dry skin, your inner thighs or your wrists as directed by your physician. You can apply it after a shower then allow it to dry completely for a few minutes before putting on your clothes. After that, wash your hands thoroughly using soap and clean water. Avoid swimming or bathing for more than two hours after this.
In case you miss a dose, take it as soon as possible or immediately you get the chance to.
You should never abuse testosterone because it can lead to numerous serious side effects like brain problems, heart problems, depression, stroke, liver problems and infertility.