Enclomiphene vs hCG: Drug Comparison

Enclomiphene is a non-steroidal selective estrogen receptor modulator (SERM) sometimes used to treat male secondary hypogonadism, or low testosterone caused by problems with the hypothalamus or pituitary gland. The medication is derived from another SERM called clomiphene citrate, and while enclomiphene is not approved by the United States Food and Drug Administration (FDA) to treat any condition on its own, it is available through compounding pharmacies.

Enclomiphene is designed to stimulate testosterone production while minimizing the estrogenic side effects sometimes seen with clomiphene, such as breast tissue growth. It works by blocking estrogen signals in the brain, which increases the release of certain hormones, like luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These hormones then tell the testicles to produce more natural testosterone.

Enclomiphene is taken as a daily pill, usually in doses of 12.5 milligrams (mg) to 25 mg.

Enclomiphene boosts testosterone while helping the body maintain its natural hormone production and sperm count, making it a good alternative to traditional testosterone replacement therapies for men who want to preserve their fertility.

Human chorionic gonadotropin, or hCG, is an injectable medication used to treat male hypogonadism (low testosterone). The medication mimics the action of luteinizing hormone (LH), signaling the Leydig cells in the testes to produce more testosterone. hCG is self-administered on a scheduled basis. Common side effects include gynecomastia (breast enlargement), swelling at the injection site, and nausea.

Selective estrogen receptor modulator

Gonadotropin

Enclomiphene is not approved as a drug in the United States

Pregnyl (chorionic gonadotropin) is indicated for:

• Prepubertal cryptorchidism not due to anatomical obstruction

• Selected cases of hypogonadotropic hypogonadism (hypogonadism secondary to a pituitary deficiency) in males

• Induction of ovulation and pregnancy in the anovulatory, infertile woman in whom the cause of anovulation is secondary and not due to primary ovarian failure, and who has been appropriately treated with human gonadotropins

• Typically taken orally

• Often prescribed at 6.25 mg, 12.5 mg, and 25 mg doses

• Typically taken as an intramuscular injection. See Full Prescribing Information

Information about enclomiphene is limited

Adverse reactions include:

For males and females:

• Hypersensitivity reactions, both localized and systemic in nature, including anaphylaxis have been reported

• Irritability

• Restlessness

• Depression

• Headache

• Reactions at the site of injection, such as bruising, pain, redness, swelling and itching

• Edema

• Fatigue

In the female:

• In rare instances, thromboembolism has been associated with FSH/hCG therapy

• Hydrothorax, as a complication of severe ovarian hyperstimulation syndrome (OHSS)

• Abdominal pain and gastrointestinal symptoms such as nausea and diarrhea, related to mild OHSS

• Unwanted ovarian hyperstimulation, mild or severe OHSS

• Mild to moderate enlargement of ovaries and ovarian cysts related to mild OHSS

• Painful breasts

• Weight gain as a characteristic of severe OHSS

In the male:

• Water and sodium retention is occasionally seen after administration of high dosages

• Gynecomastia

• Precocious puberty

Information about enclomiphene is limited

• Prior hypersensitivity reactions to human gonadotropins, including hCG, or any of the excipients

• High serum FSH, indicating primary gonadal failure in women

• Presence of uncontrolled non-gonadal endocrinopathies (e.g., thyroid, adrenal, or pituitary disorders)

• Tumors of the hypothalamus or pituitary gland and ovary, breast, or uterus in females and breast or prostate in males

• Malformations of the reproductive organs incompatible with pregnancy

• Fibroid tumors of the uterus incompatible with pregnancy

• Abnormal vaginal bleeding of undetermined origin

Information about enclomiphene is limited

• Anaphylaxis

• OHSS

• Pulmonary and vascular complications

• Ovarian torsion

• Multi-fetal gestation and birth

• Congenital malformations

• Ectopic pregnancy

• Spontaneous abortion

• Ovarian neoplasms

• Induction of androgen secretion by hCG may cause fluid retention

• Use hCG with caution in patients with cardiac or renal disease, hypertension, epilepsy, migraine, or asthma

• Evaluate patients for uncontrolled non-gonadal endocrinopathies (e.g., thyroid, adrenal or pituitary disorders) and provide the appropriate specific treatment

• Pregnancy: Not indicated in pregnancy

• Breastfeeding: It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised if hCG is administered to a nursing woman

Information about enclomiphene is limited. It is the active isomer of clomiphene.

*This information is from the label for brand name Pregnyl^®. See the Full Prescribing Information for more complete information. Chorionic gonadotropin, the active ingredient in Pregnyl, may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient chorionic gonadotropin.