Enclomiphene

Important Safety Information — Enclomiphene

Regulatory status

Not FDA-approved for any use. No enclomiphene product has been approved by the FDA; an application for one was submitted to the FDA and was not approved. A licensed provider reviews your health history, current medicines and, where appropriate, lab tests before deciding whether it may be appropriate for you.

Do not use if

• are allergic to enclomiphene, clomiphene or any ingredient in the capsule;
• have liver disease or a history of liver problems (a contraindication on the label of clomiphene, the related FDA-approved medicine);
• have uncontrolled thyroid or adrenal problems (also a contraindication on the clomiphene label);
• have a pituitary tumor or other growth in the brain (also a contraindication on the clomiphene label).

Before starting, tell your provider if

• have ever had a blood clot in a leg or lung, a stroke or a mini-stroke (transient ischemic attack);
• have heart disease or an irregular heartbeat;
• have liver or kidney problems (people with these conditions had higher levels of the medicine in their blood in studies);
• have cataracts or other eye problems, or notice any change in your vision;
• have a history of prostate problems or a raised PSA, or a high red blood cell count;
• take any other prescription or over-the-counter medicines, vitamins or supplements (enclomiphene is broken down in the body mainly by the liver enzyme CYP2D6).

Serious side effects — get medical help right away

• Heart and blood-clot events. FDA reviewers listed heart and blood-clot (thromboembolic) events as a safety concern, and blood clots in the legs and lungs were reported in a six-month enclomiphene safety study. Get emergency help right away for chest pain, sudden shortness of breath or signs of a stroke.
• Vision changes. Blurred vision led some people to stop enclomiphene in studies. The clomiphene label warns that blurring, spots or flashes can occur and may be prolonged and possibly permanent. Stop and contact your provider right away for an eye check if your vision changes.
• Changes in blood tests. FDA reviewers noted increases in estradiol, PSA and hematocrit (the share of red blood cells in the blood) as safety concerns. Your provider may order blood tests to check these.
• Mood changes. Aggression led some people to stop treatment in studies, and anxiety and depression were also reported. Tell your provider about any change in mood or behavior.

Common side effects

Common side effects: headache, hot flushes, nausea, muscle spasms and dizziness were among those reported most often in studies. These are not all the possible side effects.

You may report side effects to the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Pregnancy and breastfeeding

Enclomiphene has been studied in men only and is not for use by women. The label for clomiphene, the related FDA-approved medicine, says it must not be used during pregnancy.

The long-term safety of enclomiphene has not been established. In 2018 the European Medicines Agency declined to authorize an enclomiphene product because its safety and effectiveness had not been sufficiently shown.

Prescription only. Enclomiphene is available only after an online visit with a licensed provider, who determines whether treatment is appropriate for you. This summary does not replace the full prescribing information. Not medical advice. Results may vary.