Side Effects of AndroGel (testosterone gel)

AndroGel (testosterone gel) is an androgen administered topically (on the skin) to treat low testosterone levels. 

Testosterone is the major male sex hormone responsible for the normal growth and development of the male sex organs and secondary sex characteristics.

These effects include development of the:

• prostate, penis, and scrotum;
• distribution of facial, pubic, chest and axillary hair;
• development of a deep voice and
• alterations in muscle mass and fat distribution. 

Low production of testosterone leads to erectile dysfunction, reduced sexual desire, fatigue and loss of energy, depression, regression of secondary sexual characteristics, and weakening of bones (osteoporosis). AndroGel and other testosterone replacement products supplement or replace natural production of testosterone and reverse symptoms of low testosterone.

Common side effects of AndroGel include:

• headache,
• high blood pressure,
• acne,
• abnormal lab tests (for example, glucose and cholesterol tests),
• application site reactions (for example, itching, blisters, and redness),
• enlarged prostate, and
• increased serum prostate-specific antigen (PSA) levels.

Serious side effects of AndroGel include liver problems and blood clots. 

Drug interactions of AndroGel include warfarin, which may increase the risk of bleeding. 

Testosterone may decrease blood glucose levels and less insulin may be required in diabetic patients. 

Combining steroids with testosterone may increase fluid retention. 

AndroGel should not be used in women. Women exposed to this medication may have side effects due to testosterone gel. 

AndroGel should not be used by nursing mothers because of the possibility of adverse effects in the nursing infant. Avoid contact with Androgel if you are pregnant or breastfeeding.

The most common side effects of AndroGel are:

• headache,
• high blood pressure,
• acne,
• abnormal lab tests (for example, glucose and cholesterol tests),
• application site reactions (for example, itching, blisters, and redness),
• enlarged prostate, and
• increased serum prostate-specific antigen (PSA) levels.

Clinical Trial Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Clinical Trials in Hypogonadal Men

Table 2 shows the incidence of all adverse events judged by the investigator to be at least possibly related to treatment with AndroGel 1% and reported by > 1% of patients in a 180 Day, Phase 3 study.

Table 2: Adverse Events Possibly, Probably or Definitely Related to Use of AndroGel 1% in the 180-Day Controlled Clinical Trial

Other less common adverse reactions, reported in fewer than 1% of patients included:

• amnesia,
• anxiety,
• discolored hair,
• dizziness,
• dry skin,
• hirsutism,
• hostility,
• impaired urination,
• paresthesia,
• penis disorder,
• peripheral edema,
• sweating, and
• vasodilation.

In this 180 day clinical trial, skin reactions at the site of application were reported with AndroGel 1%, but none was severe enough to require treatment or discontinuation of drug.

Six patients (4%) in this trial had adverse events that led to discontinuation of AndroGel 1%. These events included:

• cerebral hemorrhage,
• convulsion (neither of which were considered related to AndroGel 1% administration),
• depression,
• sadness,
• memory loss,
• elevated prostate-specific antigen, and
• hypertension.

No AndroGel 1% patient discontinued due to skin reactions.

In a separate uncontrolled pharmacokinetic study of 10 patients, two had adverse events associated with AndroGel 1%; these were asthenia and depression in one patient and increased libido and hyperkinesia in the other.

In a 3 year, flexible dose, extension study, the incidence of all adverse events judged by the investigator to be at least possibly related to treatment with AndroGel 1% and reported by > 1% of patients is shown in Table 3.

Table 3: Adverse Events Possibly, Probably or Definitely Related to Use of AndroGel 1% in the 3 Year, Flexible Dose, Extension Study

Two patients reported serious adverse events considered possibly related to treatment: deep vein thrombosis (DVT) and prostate disorder requiring a transurethral resection of the prostate (TURP).

Discontinuation for adverse events in this study included: two patients with application site reactions, one with kidney failure, and five with prostate disorders (including increase in serum PSA in 4 patients, and increase in PSA with prostate enlargement in a fifth patient).

Increases in Serum PSA Observed in Clinical Trials of Hypogonadal Men

During the initial 6-month study, the mean change in PSA values had a statistically significant increase of 0.26 ng/mL. Serum PSA was measured every 6 months thereafter in the 162 hypogonadal men on AndroGel 1% in the 3-year extension study. There was no additional statistically significant increase observed in mean PSA from 6 months through 36 months. However, there were increases in serum PSA observed in approximately 18% of individual patients. The overall mean change from baseline in serum PSA values for the entire group from month 6 to 36 was 0.11 ng/mL.

Twenty-nine patients (18%) met the per-protocol criterion for increase in serum PSA, defined as > 2X the baseline or any single serum PSA > 6 ng/mL. Most of these (25/29) met this criterion by at least doubling of their PSA from baseline. In most cases where PSA at least doubled (22/25), the maximum serum PSA value was still < 2 ng/mL. The first occurrence of a pre-specified, post-baseline increase in serum PSA was seen at or prior to Month 12 in most of the patients who met this criterion (23 of 29; 79%).

Four patients met this criterion by having a serum PSA > 6 ng/mL and in these, maximum serum PSA values were 6.2 ng/mL, 6.6 ng/mL, 6.7 ng/mL, and 10.7 ng/mL. In two of these patients, prostate cancer was detected on biopsy. The first patient's PSA levels were 4.7 ng/mL and 6.2 ng/mL at baseline and at Month 6/Final, respectively. The second patient's PSA levels were 4.2 ng/mL, 5.2 ng/mL, 5.8 ng/mL, and 6.6 ng/mL at baseline, Month 6, Month 12, and Final, respectively.

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of AndroGel 1%. Because the reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure (Table 4).

Table 4: Adverse Drug Reactions from Postmarketing Experience of AndroGel 1% by MedDRA System Organ Class

Secondary Exposure to Testosterone in Children

Cases of secondary exposure to testosterone resulting in virilization of children have been reported in postmarket surveillance. Signs and symptoms of these reported cases have included:

• enlargement of the clitoris (with surgical intervention) or the penis,
• development of pubic hair,
• increased erections and libido,
• aggressive behavior, and
• advanced bone age.

In most cases with a reported outcome, these signs and symptoms were reported to have regressed with removal of the testosterone gel exposure. In a few cases, however, enlarged genitalia did not fully return to age-appropriate normal size, and bone age remained modestly greater than chronological age.

In some of the cases, direct contact with the sites of application on the skin of men using testosterone gel was reported. In at least one reported case, the reporter considered the possibility of secondary exposure from items such as the testosterone gel user's shirts and/or other fabric, such as towels and sheets.

Insulin

Changes in insulin sensitivity or glycemic control may occur in patients treated with androgens. In diabetic patients, the metabolic effects of androgens may decrease blood glucose and, therefore, may decrease insulin requirements.

Oral Anticoagulants

Changes in anticoagulant activity may be seen with androgens, therefore more frequent monitoring of international normalized ratio (INR) and prothrombin time are recommended in patients taking anticoagulants, especially at the initiation and termination of androgen therapy.

Corticosteroids

The concurrent use of testosterone with adrenocorticotropic hormone (ACTH) or corticosteroids may result in increased fluid retention and requires careful monitoring particularly in patients with cardiac, renal or hepatic disease.

Drug Abuse And Dependence

Controlled Substance

AndroGel 1% contains testosterone, a Schedule III controlled substance in the Controlled Substances Act.

Abuse

Anabolic steroids, such as testosterone, are abused. Abuse is often associated with adverse physical and psychological effects.

Dependence

Although drug dependence is not documented in individuals using therapeutic doses of anabolic steroids for approved indications, dependence is observed in some individuals abusing high doses of anabolic steroids. In general, anabolic steroid dependence is characterized by any three of the following:

• Taking more drug than intended
• Continued drug use despite medical and social problems
• Significant time spent in obtaining adequate amounts of drug
• Desire for anabolic steroids when supplies of the drugs are interrupted
• Difficulty in discontinuing use of the drug despite desires and attempts to do so
• Experience of a withdrawal syndrome upon discontinuation of anabolic steroid use