Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ANDROGEL vs ENZALUTAMIDE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Androgen receptor agonist; testosterone replacement therapy to restore serum testosterone to physiologic levels.
Androgen receptor inhibitor; binds to the androgen receptor and inhibits androgen receptor nuclear translocation, DNA binding, and coactivator recruitment.
Primary hypogonadism (congenital or acquired),Hypogonadotropic hypogonadism,Off-label: delayed puberty in males, certain breast cancers
Treatment of metastatic castration-resistant prostate cancer,Treatment of metastatic castration-sensitive prostate cancer
50 mg (5 g gel) applied topically once daily, preferably in the morning. Dose may be adjusted between 25 mg (2.5 g gel) and 100 mg (10 g gel) based on serum testosterone levels.
160 mg orally once daily
The terminal elimination half-life of testosterone from Andro Gel is approximately 10-12 hours when applied topically, but due to continuous absorption from the skin depot, serum levels are sustained over 24 hours, allowing once-daily dosing.
Terminal elimination half-life is approximately 5.8 days (range 2.8–10.2 days) after steady state; supports once-daily dosing.
Hepatic via CYP3A4, CYP2C9, and 17β-hydroxysteroid dehydrogenase; metabolites include estradiol and dihydrotestosterone.
Primarily metabolized by CYP2C8 and CYP3A4; forms active metabolite N-desmethyl enzalutamide
Approximately 90% of a topical dose is excreted in urine as conjugated and unconjugated metabolites, with about 6% excreted in feces via bile; renal elimination is the primary route.
Primarily hepatic metabolism; ~70% of dose excreted in feces (as unchanged drug and metabolites), ~1% in urine as unchanged drug. Biliary excretion is a major route.
Approximately 98% of circulating testosterone is protein-bound: 40-50% bound to sex hormone-binding globulin (SHBG) and 50-60% loosely bound to albumin.
97–98% bound to plasma proteins, primarily albumin and alpha-1-acid glycoprotein.
The apparent volume of distribution of testosterone is about 1.0 L/kg, reflecting extensive distribution into tissues, particularly muscle, skin, and male reproductive organs.
Approximately 110 L (1.1 L/kg for a 70 kg patient); indicates extensive extravascular distribution.
Bioavailability of testosterone from Andro Gel is approximately 10-14% of the applied dose, due to limited skin permeation and first-pass metabolism (though minimal with transdermal route). For comparison, oral testosterone bioavailability is <1%, while intramuscular testosterone enanthate has 100% bioavailability.
Oral bioavailability is not published; absorption is at least moderate based on systemic exposure. Food does not significantly affect absorption.
No specific dose adjustment is provided for renal impairment. Use with caution in patients with severe renal impairment due to potential for fluid retention.
No dose adjustment required for mild to moderate renal impairment (e GFR 30-89 m L/min). Insufficient data for severe renal impairment (e GFR <30 m L/min) or end-stage renal disease.
Contraindicated in patients with Child-Pugh class C (severe hepatic impairment). Use with caution and monitor liver function in mild to moderate hepatic impairment; no specific dose reduction guidelines exist.
No dose adjustment for mild hepatic impairment (Child-Pugh A). For moderate (Child-Pugh B): reduce dose to 80 mg once daily. Not recommended for severe (Child-Pugh C).
Not indicated in pediatric patients under 18 years of age; safety and efficacy have not been established.
Not approved for use in pediatric patients; safety and efficacy not established.
Elderly patients may be more sensitive to androgens, and require careful monitoring for prostate enlargement, prostate cancer, and fluid retention. Start at the lowest dose (25 mg daily) and titrate based on serum testosterone levels and clinical response.
No specific dose adjustment required; elderly patients may be more susceptible to adverse effects such as falls, fractures, and hypertension. Monitor closely.
None.
None
Risk of secondary exposure to testosterone (children) – avoid skin contact,Polycythemia (monitor hematocrit),Prostate enlargement/cancer risk,Cardiovascular risk (especially in elderly),Spermatogenesis suppression,Hepatic effects (monitor liver function),Edema (in patients with preexisting conditions)
Seizure risk,Posterior reversible encephalopathy syndrome (PRES),Hypersensitivity reactions including angioedema,Increased risk of falls and fractures,Embryo-fetal toxicity
Known hypersensitivity to testosterone or gel components,Prostate cancer,Breast cancer (males),Women who are pregnant or may become pregnant (risk to fetus)
Pregnancy,Concomitant use with strong CYP2C8 inhibitors or inducers,Concomitant use with strong CYP3A4 inducers
No specific food interactions. Grapefruit juice may increase testosterone levels due to CYP3A4 inhibition, but clinical significance is unclear. Avoid excessive alcohol intake as it may affect testosterone levels and liver function.
No significant food interactions. Avoid grapefruit juice as it may increase enzalutamide levels (minor interaction). Take with or without food.
Andro Gel (testosterone) is contraindicated in pregnancy. Testosterone is a teratogen with masculinization of female fetuses (clitoral enlargement, labial fusion, urogenital sinus abnormalities) when exposed during the first trimester. Second and third trimester exposure may cause pseudohermaphroditism in females. Risk is highest during the first 12 weeks of gestation.
Enzalutamide is contraindicated in pregnancy. Based on its mechanism of action (androgen receptor inhibitor), there is a high risk of fetal harm, particularly male pseudohermaphroditism and impaired reproductive development. Use should be avoided in all trimesters. Women of childbearing potential must use effective contraception during treatment and for 1 month after the last dose.
Testosterone is excreted into breast milk with an estimated M/P ratio of 0.1-0.3. It may cause virilization in nursing infants. Breastfeeding is not recommended during Andro Gel therapy.
No human data available. Enzalutamide and its active metabolite are likely excreted into human milk. Due to the potential for serious adverse reactions in the breastfed infant, breastfeeding is not recommended during treatment and for 1 month after the last dose. M/P ratio is unknown.
Andro Gel is contraindicated in pregnancy; no dose adjustments are applicable. If exposure occurs, discontinue immediately and monitor for fetal effects.
Enzalutamide is contraindicated in pregnancy; therefore, no dose adjustments are recommended. If exposure occurs, discontinue the drug and manage according to clinical judgment. Pregnancy induces metabolic changes (e.g., increased hepatic clearance, plasma volume expansion) that could theoretically reduce exposure, but no data exist to support a specific dose adjustment.
Apply to clean, dry, intact skin on shoulders, upper arms, or abdomen. Avoid application to genitals or chest due to higher absorption and risk of transfer. Wash hands after application. Allow gel to dry before dressing. Monitor serum testosterone, hematocrit, PSA, and lipid profile. Contraindicated in men with breast or prostate cancer. May cause erythrocytosis, sleep apnea, or worsening of BPH. Risk of testosterone transfer to women or children; cover application site or wash skin before contact.
Monitor for seizure risk, especially in patients with predisposing factors; enzalutamide may cause hypertension, so check blood pressure regularly; it significantly induces CYP3A4, reducing efficacy of oral contraceptives and other CYP3A4 substrates; use with caution in patients with history of cardiovascular disease; discontinue 5 half-lives before starting another antiandrogen.
Apply Andro Gel once daily at the same time each morning to clean, dry, intact skin on shoulders, upper arms, or abdomen.,Do not apply to genitals or chest.,Wash hands thoroughly with soap and water after application.,Allow gel to dry completely before dressing or coming into contact with others.,Avoid swimming, showering, or bathing for at least 5 hours after application.,If skin contact with another person is likely, cover the application site with clothing or wash the area before contact.,Keep Andro Gel away from children and women of childbearing potential.,Report any signs of deep vein thrombosis (leg swelling, pain, warmth), heart attack (chest pain, shortness of breath), or stroke (sudden weakness, confusion, vision changes).,Regular blood tests are required to monitor testosterone levels, red blood cell count, prostate health, and cholesterol.,Andro Gel may interact with blood thinners (e.g., warfarin) and corticosteroids; inform all healthcare providers.
Take the capsules whole, with or without food, at the same time each day.,Do not crush, chew, or open the capsules.,Report any signs of seizure (e.g., convulsions, loss of consciousness) to your doctor immediately.,Enzalutamide may raise your blood pressure; have it checked regularly.,Use effective non-hormonal contraception during treatment and for 3 months after stopping; hormonal contraceptives may not work.,This drug may cause fatigue, falls, and fractures; avoid activities requiring alertness until you know how it affects you.,Notify your doctor if you experience chest pain, shortness of breath, or leg swelling.,Seek immediate medical attention for symptoms of posterior reversible encephalopathy syndrome (PRES): headache, confusion, visual disturbances.
No interactions on record
"Rifaximin is a non-systemic antibiotic with minimal oral absorption (<0.4%), thus is not expected to significantly affect systemic drug metabolism. However, in vitro studies suggest rifaximin can induce the expression of CYP3A4, the major enzyme responsible for the metabolism of enzalutamide. Although clinical data are limited, coadministration could theoretically decrease enzalutamide exposure, reducing its efficacy in treating prostate cancer; conversely, the baseline description suggests an increase, but evidence is conflicting."
"Enzalutamide, a potent CYP3A4 inducer, significantly reduces the exposure of diclofenac, a CYP2C9 substrate, by increasing its hepatic metabolism. This interaction can lead to subtherapeutic diclofenac concentrations, thereby diminishing its analgesic and anti-inflammatory efficacy. Clinically, patients may experience inadequate pain control or exacerbation of inflammatory conditions, such as arthritis, when these agents are coadministered."
"Enzalutamide, a potent androgen receptor inhibitor, significantly induces CYP3A4 and other drug-metabolizing enzymes. Dienogest, a progestin used in endometriosis and contraception, is primarily metabolized by CYP3A4. Coadministration leads to markedly reduced dienogest plasma concentrations, potentially diminishing its therapeutic efficacy in managing endometriosis symptoms or contraceptive effectiveness."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ANDROGEL vs ENZALUTAMIDE, answered by our medical review team.
ANDROGEL is a Androgen that works by Androgen receptor agonist; testosterone replacement therapy to restore serum testosterone to physiologic levels.. ENZALUTAMIDE is a Androgen Receptor Inhibitor that works by Androgen receptor inhibitor; binds to the androgen receptor and inhibits androgen receptor nuclear translocation, DNA binding, and coactivator recruitment.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ANDROGEL and ENZALUTAMIDE depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ANDROGEL is: 50 mg (5 g gel) applied topically once daily, preferably in the morning. Dose may be adjusted between 25 mg (2.5 g gel) and 100 mg (10 g gel) based on serum testosterone levels.. The standard adult dose of ENZALUTAMIDE is: 160 mg orally once daily. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between ANDROGEL and ENZALUTAMIDE in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. ANDROGEL is classified as Category C. AndroGel (testosterone) is contraindicated in pregnancy. Testosterone is a teratogen with masculinization of female fetuses (clitoral enlargement, labial fusion, urogenital sinus a. ENZALUTAMIDE is classified as Category D/X. Enzalutamide is contraindicated in pregnancy. Based on its mechanism of action (androgen receptor inhibitor), there is a high risk of fetal harm, particularly male pseudohermaphrod. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.