BMA Concise Guide to Medicine & Drugs

Clomifene

Brand name Clomid

Used in the following combined preparations None

QUICK REFERENCE

Drug group Drug for infertility

Overdose danger rating Low

Dependence rating Low

Prescription needed Yes

Available as generic Yes

GENERAL INFORMATION

Clomifene is used to treat female infertility due to failure of ovulation. It stimulates ovulation by increasing production of hormones by the hypothalamus and pituitary gland. Tablets are taken within about five days of the onset of each menstrual cycle. If clomifene does not stimulate ovulation after several months, other drugs may be prescribed.

Multiple pregnancies (usually twins) occur more commonly in women treated with clomifene. Adverse effects include an increased risk of ovarian cysts and ectopic pregnancy. Ovarian hyperstimulation syndrome (overstimulation of the ovaries) has also been reported; symptoms include pain and swelling of the abdomen, swelling of the hands and legs, shortness of breath, weight gain, nausea, and vomiting. You should consult your doctor if any of these symptoms develop.

INFORMATION FOR USERS

Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Tablets.

Frequency and timing of doses Once daily for 5 days during each menstrual cycle, preferably starting on day 2 of the cycle.

Dosage range 50mg daily initially; dose may be increased up to 100mg daily.

Onset of effect Ovulation occurs 11–12 days after the last dose in any cycle. However, ovulation may not occur for several months.

Duration of action 5 days.

Diet advice None.

Storage Keep in original container at room temperature out of the reach of children. Protect from light.

Missed dose Take as soon as you remember. If your next dose is due at this time, take the missed dose and the next scheduled dose together.

Stopping the drug Take as directed by your doctor. Stopping the drug will reduce the chances of conception.

Exceeding the dose An occasional unintentional extra dose is unlikely to be a cause for concern. But if you notice any unusual symptoms, or if a large overdose has been taken, notify your doctor.

POSSIBLE ADVERSE EFFECTS

Most side effects are related to the dose. Common side effects include hot flushes and breakthrough bleeding, which should be reported to your doctor if severe, nausea, vomiting, and abdominal discomfort or bloating, which should be notified to your doctor in all cases. More rarely, there may be breast tenderness, dryness of the skin, hair loss, rash, or dizziness; if any of these occur, discuss with your doctor. Ovarian enlargement and cyst formation my also sometimes occur but usually resolve within a few weeks of stopping the drug. If blurred vision, seizures, limb swelling, shortness of breath, or severe pain in the chest or abdomen occur, stop taking the drug and consult your doctor.

INTERACTIONS

None.

SPECIAL PRECAUTIONS

Be sure to tell your doctor if:

· You have a long-term liver problem.

· You are pregnant.

· You have uterine fibroids or abnormal vaginal bleeding.

· You are taking other medicines.

Pregnancy Not prescribed. The drug is stopped as soon as pregnancy occurs.

Breast-feeding Not prescribed.

Infants and children Not prescribed.

Over 60 Not prescribed.

Driving and hazardous work Avoid such activities until you have learned how clomifene affects you because the drug can cause blurred vision.

Alcohol Keep consumption low.

PROLONGED USE

Prolonged use of clomifene may cause visual impairment. Also, no more than 6 courses of treatment are recommended since this may lead to an increased risk of ovarian cancer.

Monitoring Eye tests may be recommended if symptoms of visual impairment are noticed. Monitoring of body temperature and blood or urine hormone levels, or ultrasound scans of the ovaries are performed to detect signs of ovulation and pregnancy.