Enclomiphene
Prompts your body to make its own testosterone. Enclomiphene is a daily capsule for men with low testosterone whose testes still work but aren’t getting a strong enough signal from the brain. It blocks estrogen’s feedback in the brain, which raises LH and FSH, the hormones that tell the testes to make testosterone and sperm. In short trials it raised testosterone into the normal range for most men, and sperm counts held steady on average, while on testosterone gel they fell. The trials didn’t measure symptoms like energy or sex drive, and it isn’t FDA-approved. Your provider starts with bloodwork and sets your dose from your labs.
- Bloodwork before you start, and to set your dose
- One capsule a day, 12.5 mg to start
- In trials, sperm counts held steady on average; on testosterone gel they fell
Daily capsule · from $99/mo. Prices are preliminary.
How to use it
- Take one capsule a day, at about the same time each day, with or without food.
- Get your follow-up bloodwork on time. Your provider uses it to set your dose, usually after 4 to 6 weeks.
- Stop and get medical help right away for vision changes (blurring, spots or flashes), pain or swelling in one leg, chest pain or sudden shortness of breath.
- Form
- Capsule, 30 per bottle
- Strength
- Enclomiphene citrate 12.5 mg; your provider may adjust to 6.25 or 25 mg
- Typical use
- One capsule a day
- Labs
- Before you start, after 4 to 6 weeks, then every 6 to 12 months
- Who it’s for
- Men 18 and older with low testosterone on two morning blood tests, and LH and FSH that aren’t high
One active ingredient.
- Enclomiphene citrate (12.5 mg): One of the two forms that make up clomiphene, a fertility drug for women. Enclomiphene on its own isn’t FDA-approved. It blocks estrogen’s feedback in the brain, which raises LH and FSH, the signals that tell the testes to make testosterone and sperm.
What the research does and doesn’t show
What it shows: in two 16-week trials of 256 overweight men aged 18 to 60 with low testosterone, average testosterone rose from about 205 ng/dL to the low 400s on enclomiphene, into the normal range for most men. Sperm counts held steady on average, while on testosterone gel they fell.
What it doesn’t show: the trials measured testosterone levels, not how men felt. Energy, sex drive, erections, mood and quality of life weren’t measured, and a 48-week study found no difference in lean muscle compared with placebo. Sperm counts dropped by half or more in some men, and no study has looked at pregnancies. The trials were short, run by the drug’s maker and mostly in men with obesity, and they didn’t use compounded capsules. There’s no long-term safety data on the heart, blood clots or the eyes.
So enclomiphene can raise testosterone in men like those studied. Whether that changes how you feel hasn’t been shown.
Studies: Kim 2016, ZA-304/305, 16 weeks, 256 overweight men 18-60 (PMID 26496621) https://pubmed.ncbi.nlm.nih.gov/26496621/ (total T about 205 to 413-446 ng/dL; gel 351-387; placebo 214-236; sperm +12 to 15% vs -33 to -57% on gel). ZA-301/302 results posted on ClinicalTrials.gov, unpublished (fact sheet section 3): about 80% reached normal testosterone; 14% had a 50% or greater drop in sperm concentration vs 3-4% on placebo. ZA-205, 48 weeks: lean mass not different from placebo (fact sheet section 3). FDA questioned assay validation; trials sponsor-run (fact sheet section 3). EMA refused EnCyzix in 2018 partly because symptoms weren’t studied (EMA/CHMP/54473/2018). Never “clinically proven”, “doubles your T” or “TRT without testosterone” (fact sheet section 7).
What to expect
- Weeks 1–4
- Testosterone starts to rise. Headache, hot flashes or nausea can happen and often ease.
- Weeks 4–6
- Follow-up bloodwork. Your provider may adjust your dose based on your testosterone level.
- Ongoing
- Bloodwork every 6 to 12 months, including hematocrit and, depending on your age, PSA. Refills ship monthly.
Important safety information
Before you start
Your provider reviews your health history, medicines and allergies before prescribing, and prescribes only if it’s right for you. Tell your care team about any side effect, and get emergency care for chest pain, trouble breathing, or swelling of the face, lips or throat.
Side effects, and when to get help
Headache, hot flashes, nausea, dizziness, muscle spasms and mood changes like irritability, anxiety or low mood have been reported. They often ease. Get help right away for vision changes, pain or swelling in one leg, chest pain or sudden shortness of breath.
Is it FDA-approved?
No. An application to approve enclomiphene was turned down in 2015, and it isn’t an FDA-approved drug. It’s compounded: prepared by a licensed pharmacy for you individually, under an FDA policy that currently allows compounding it while the FDA reviews it. The FDA doesn’t review compounded medicines for safety, effectiveness or quality. A licensed provider decides whether it’s appropriate for you.
About Enclomiphene
How is it different from testosterone therapy?
Testosterone therapy adds testosterone from outside. Your brain responds by turning down LH and FSH, so the testes make less of their own testosterone and sperm. Enclomiphene raises LH and FSH instead, so the testes make more. In 16-week trials, sperm counts held steady on average with enclomiphene and fell with testosterone gel. Enclomiphene isn’t FDA-approved, and it has much less long-term safety data than testosterone.
Will it help my energy, sex drive or muscle?
The trials measured testosterone levels, not how men felt, so that hasn’t been shown. One 48-week study found no difference in lean muscle compared with placebo. Your provider can talk through what to expect for you.
What bloodwork do I need?
Low testosterone is confirmed with two early-morning tests. Your provider also checks LH, FSH and prolactin to find the cause, and your hematocrit, plus PSA if you’re 40 or older. After you start, testosterone is rechecked at 4 to 6 weeks to set your dose, then every 6 to 12 months.
Will it affect my fertility?
In trials, sperm counts held steady on average over 16 weeks, unlike with testosterone gel. But counts dropped by half or more in some men, and no study has looked at pregnancies. If you’re trying to conceive, tell your provider.
What are the risks?
Headache, hot flashes, nausea, dizziness and mood changes like irritability are the most common. Rarely, enclomiphene has caused vision changes and blood clots. It can also raise estradiol, hematocrit and PSA, which is why your provider checks your bloodwork. Get help right away for vision changes, pain or swelling in one leg, chest pain or sudden shortness of breath.
Is it FDA-approved?
No. An application to approve enclomiphene was turned down in 2015, and it isn’t an FDA-approved drug. It’s compounded: prepared by a licensed pharmacy for you individually, under an FDA policy that currently allows compounding it while FDA reviews it. The FDA doesn’t review compounded medicines for safety, effectiveness or quality. A licensed provider decides whether it’s appropriate for you.