Clomifene

Sounds like 'KLOE-mi-feen'

Clomifene is mainly used to treat infertility in women. Find out how to take it safely and the possible side effects. Clomifene is also called Clomid or Clomiphene.

Type of medicine Also called
  • It belongs to a group of medicines known as anti-oestrogens
  • Clomiphene
  • Clomid®

What is clomifene?

Clomifene is mainly used to treat infertility in women who don't ovulate or have irregular periods. For infertility, clomifene works by stimulating the release of eggs from the ovary (a process called ovulation). 

Clomifene belongs to a group of medicines known as anti-oestrogens. It suppresses the amount of oestrogen in the body, and in this way ‘tricks’ the pituitary gland (in the brain) into producing more hormones that stimulate the ovary to ripen and release an egg.

Multiple births are possible with clomifene – about 10% of pregnancies from clomiphene treatment are twins, and about 1% are triplets. Quadruplets or more are possible but very rare.

Dose

  • In Aotearoa New Zealand clomifene is available as 50 mg tablets. 
  • The usual starting dose of clomifene is 1 tablet (50 mg) taken once daily for a 5 day course. It is usually started by a specialist doctor.
  • Your dose may be increased to 2 tablets daily on following courses if your doctor thinks this is necessary.
  • Always take your clomifene exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much clomifene to take, how often to take it, and any special instructions.

How to take clomifene 

  • When to start the course: If you have a menstrual bleed (period), your course is usually started on day 5 of the cycle. If you have not had a menstrual bleed it can be started at any time.
  • Following courses are started at least 30 days after the previous course. You will not usually need to take more than 3 courses of treatment but no more than 6 courses in total should be taken.
  • Timing: Take clomifene at the same time each day on each of the 5 days. Swallow the tablet whole with a drink of water. You can take clomifene with or without food.
  • Missed dose: If you forget to take your dose, talk to your doctor, as you may need to change your treatment cycle. Do not take 2 doses to make up for a missed dose.

What to consider before starting clomifene

  • Do you think you may already be pregnant?
  • Do you have liver problems?
  • Do you have ovarian cysts or uterine fibroids?
  • Are you taking any herbal supplements or rongoā Māori?

If you answered yes to any of these questions it’s important that you tell your doctor or pharmacist before you start clomifene. Sometimes a medicine isn’t suitable for a person with certain conditions, or it can only be used with extra care.

What are the side effects of clomifene?

Like all medicines, clomifene can cause side effects, although not everyone gets them. Often unwanted side effects improve as your body gets used to the new medicine.

Side effects What should I do?
  • Feeling flushed
  • Hot flushes
  • Headache
  • Dizziness
  • Feeling sick (nausea)
  • These are quite common when you start taking clomifene.
  • Tell your doctor if they bother you.
  • Blurred vision
  • Problems with your eyesight
  • Spots or flashes in front of your eyes
  • Be careful when driving or using tools until you know how this medicine affects you.
  • Tell your doctor if they bother you.
  • Pain in the stomach or abdomen
  • Feeling bloated
  • Vaginal bleeding  
  • Tell your doctor immediately or ring Healthline 0800 611 116.
 
  • Signs of problems with your liver such as yellowing of the skin or eyes, dark urine, pain in the abdomen
 
  • Tell your doctor immediately or ring Healthline 0800 611 116.
  • Signs of a stroke such as numbness, weakness or paralysis on one side of the body, slurred speech, sudden blurred vision, confusion or unsteadiness
  • Tell your doctor immediately or ring Healthline 0800 611 116.
  • Rare reports of ovarian cancer when clomifene is taken for longer than 6 cycles.
  • Speak to your doctor if you have taken 6 cycles of clomifene.
For more information on side effects, see the Medsafe consumer information leaflet Clomid.

Did you know that you can report a medicine side effect to the Centre for Adverse Reactions Monitoring (CARM)? Report a side effect to a product

Learn more

The following links have more information on clomifene. 

Clomid Consumer Information Leaflet, NPS MedicinesWise, Australia
Clomifene Patient Info, NZ

References

Clomifene citrate NZ Formulary
Clomid Product Datasheet EMC, UK

Additional resources for healthcare professionals

Clomifene and risk of stroke Medsafe, NZ, 2015
Understanding polycystic ovary syndrome BPAC, NZ, 2008

Credits: Sandra Ponen, Pharmacist. Reviewed By: Maya Patel, MPharm PGDipClinPharm, Auckland Last reviewed: 09 Feb 2022