Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
PREGNYL vs ANDROGEL
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Human chorionic gonadotropin (h CG) acts as a luteinizing hormone (LH) agonist, binding to LH receptors in the gonads, stimulating testosterone production in males and ovulation in females.
Androgen receptor agonist; testosterone replacement therapy to restore serum testosterone to physiologic levels.
FDA: Treatment of prepubertal cryptorchidism,FDA: Induction of ovulation and pregnancy in anovulatory infertile women,Off-label: Hypogonadotropic hypogonadism in males,Off-label: Assisted reproductive technology (ART) protocols
Primary hypogonadism (congenital or acquired),Hypogonadotropic hypogonadism,Off-label: delayed puberty in males, certain breast cancers
Intramuscular injection: 5,000-10,000 IU once weekly for 4-9 weeks for ovulation induction; 1,000-2,000 IU three times weekly for spermatogenesis.
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.
Terminal elimination half-life: 23–24 hours; clinically, supports daily or every-other-day dosing; peak effect may lag due to prolonged absorption
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.
Primarily renal metabolism and excretion; limited hepatic metabolism.
Hepatic via CYP3A4, CYP2C9, and 17β-hydroxysteroid dehydrogenase; metabolites include estradiol and dihydrotestosterone.
Renal: 10-20% as unchanged drug; hepatic metabolism to inactive metabolites; fecal excretion negligible (<5%)
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.
~80% bound primarily to albumin; minor binding to sex hormone-binding globulin (SHBG)
Approximately 98% of circulating testosterone is protein-bound: 40-50% bound to sex hormone-binding globulin (SHBG) and 50-60% loosely bound to albumin.
0.5–0.7 L/kg; moderately distributed into extracellular fluid; penetrates gonadal tissues
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.
Intramuscular: ~100%; Subcutaneous: comparable (~95-100%); Oral: <5% (not used)
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.
No specific guidelines; use with caution in severe renal impairment (Cr Cl <30 m L/min) due to limited data.
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 specific guidelines for Child-Pugh; use with caution in severe hepatic impairment.
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.
Not indicated for prepubertal children; for delayed puberty in males: 1,000-2,000 IU intramuscularly 2-3 times weekly for 3-6 months.
Not indicated in pediatric patients under 18 years of age; safety and efficacy have not been established.
No specific recommendations; use lowest effective dose due to potential increased sensitivity and comorbidities.
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 FDA black box warning.
None.
Ovarian hyperstimulation syndrome (OHSS) in women,Arterial thromboembolism,Precocious puberty in males,Fluid retention,Ovarian enlargement or cyst rupture
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)
Hypersensitivity to h CG or any component,Premature epiphyseal closure in males,Androgen-dependent neoplasia (e.g., prostate cancer),Undiagnosed uterine bleeding,Ovarian cyst or enlargement due to polycystic ovarian syndrome (PCOS),Active thromboembolic disorders
Known hypersensitivity to testosterone or gel components,Prostate cancer,Breast cancer (males),Women who are pregnant or may become pregnant (risk to fetus)
No known clinically significant food interactions. Maintain usual diet unless advised otherwise by physician.
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.
Pregny (h CG) is not indicated for use during pregnancy. h CG is used to induce ovulation and is not continued after conception. In animal studies, high doses have shown fetal abnormalities, but human data are insufficient. First trimester: No direct fetal risk from therapeutic use as it is discontinued before implantation. Second/Third trimester: Not used. Overall, classified as FDA Pregnancy Category X for ovulation induction (contraindicated in pregnancy) but no teratogenic risk if discontinued before conception.
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.
Human chorionic gonadotropin (h CG) is normally present in breast milk in low concentrations. Exogenous h CG is likely excreted into breast milk, but the M/P ratio is not established. Due to lack of data and potential for adverse effects in the infant (e.g., hormonal disruption), breastfeeding is not recommended during therapy. The manufacturer advises discontinuing breastfeeding or avoiding the drug.
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.
Pregny is contraindicated in pregnancy. No dose adjustment is applicable as it is discontinued prior to conception. There are no pharmacokinetic data for pregnancy, but the drug is not used during gestation.
Andro Gel is contraindicated in pregnancy; no dose adjustments are applicable. If exposure occurs, discontinue immediately and monitor for fetal effects.
Pregnyl (h CG) is used to trigger final follicular maturation and ovulation in assisted reproduction. Monitor for ovarian hyperstimulation syndrome (OHSS); consider withholding h CG if estradiol >4000 pg/m L or >20 follicles per ovary. Administer exactly 36 hours before oocyte retrieval. Intramuscular injection into gluteal muscle; rotate sites if repeated doses.
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.
Use Pregnyl exactly as prescribed to trigger ovulation; timing is critical for egg retrieval.,Report severe pelvic pain, bloating, nausea, or rapid weight gain (possible OHSS) immediately.,Avoid pregnancy tests during treatment as h CG may cause false positive.,May cause injection site pain or swelling; apply warm compress if needed.,Do not discontinue without consulting your fertility specialist.
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.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about PREGNYL vs ANDROGEL, answered by our medical review team.
PREGNYL is a Gonadotropin Hormone that works by Human chorionic gonadotropin (h CG) acts as a luteinizing hormone (LH) agonist, binding to LH receptors in the gonads, stimulating testosterone production in males and ovulation in females.. ANDROGEL is a Androgen that works by Androgen receptor agonist; testosterone replacement therapy to restore serum testosterone to physiologic levels.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between PREGNYL and ANDROGEL 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 PREGNYL is: Intramuscular injection: 5,000-10,000 IU once weekly for 4-9 weeks for ovulation induction; 1,000-2,000 IU three times weekly for spermatogenesis.. 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.. 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 PREGNYL and ANDROGEL 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. PREGNYL is classified as Category C. Pregny (hCG) is not indicated for use during pregnancy. hCG is used to induce ovulation and is not continued after conception. In animal studies, high doses have shown fetal abnorm. 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. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.