The degree of absorption of testosterone through the skin varies from about 9% to 14% of the applied dose.
After absorption through the skin, testosterone enters the systemic circulation in relatively constant concentrations for 24 hours.
The concentration of testosterone in serum increases from the first hour after the use of the drug Androgel, reaching a constant value from the second day of treatment. Daily fluctuations in testosterone concentrations have the same amplitude as changes in the content of endogenous testosterone observed in circadian rhythms. With the external route of administration of the drug, there are no supraphysiological peaks in the concentration of testosterone in the blood that occur during the injection method of administration. In contrast to oral androgen therapy, the external use of the drug does not cause an increase in the concentration of steroids in the liver above physiological norms.
The use of 5 g of Androgel causes an average increase in plasma testosterone concentration by approximately 2.5 ng / ml (8.7 nmol / L).
After discontinuation of treatment, the concentration of testosterone begins to decrease approximately 24 hours after the last dose. Concentration returns to baseline approximately 72-96 hours after the last dose.
The main active metabolites of testosterone are dihydrotestosterone and estradiol.
Androgel is excreted mainly with urine and with feces in the form of conjugated testosterone metabolites.