How and when to take ferrous sulfate - Brand name: Ironorm Drops

If you or your child are prescribed ferrous sulfate, follow a doctor's instructions about how and when to take it.

If you buy ferrous sulfate from a pharmacy, follow the instructions that come with the packet.

Dosage and strength

Ferrous sulfate comes as 200mg tablets, or as drops containing 125mg of ferrous sulfate in 1ml.

Your dose of ferrous sulfate depends on why you're taking it and whether you take tablets or drops.

Dose to treat anaemia

The usual dose for adults is:

• tablets – one 200mg tablet usually once a day, but it may be 2 to 3 times a day. If you get side effects your doctor may advise you to take it on alternate days
• drops – 4ml, taken once or twice a day

For children aged 12 to 17 years, the doctor will use your child's age and blood results to work out the right dose of ferrous sulfate. For children under 12 years old, the doctor will also use your child's weight to work out the right dose.

Dose to prevent anaemia

The usual dose for adults is:

• tablets – one 200mg tablet, taken once a day
• drops – 2.4ml to 4.8ml, taken once a day

For children aged 12 to 17 years, the doctor will use your child's age and blood results to work out the right dose of ferrous sulfate. For children under 12 years, the doctor will also use your child's weight to work out the right dose.

How to take it

Ferrous sulfate works best when you take it on an empty stomach. If you can, take it 30 minutes before eating, or 2 hours after eating. But if it upsets your stomach, you can take it with or after food.

A doctor (or a pharmacist) may recommend taking ferrous sulfate with orange juice or a vitamin C supplement. Vitamin C is believed to increase the amount of iron absorbed by the body.

Swallow the tablet whole with a drink of water. Do not suck, chew or keep the tablet in your mouth as this can cause mouth ulcers or stain your teeth.

Do not take it with tea, coffee, eggs or dairy products, as they can reduce the amount of iron that gets into your system. When you take ferrous sulfate (or when you eat foods that are high in iron), leave a 2-hour gap before having these foods or drinks.

If you have difficulty swallowing the tablets tell your doctor or pharmacist.

The drops may be easier for children and people who find it difficult to swallow tablets.

If you're taking ferrous sulfate as drops, it will come with a plastic syringe or dropper to help you measure out the right dose. If you do not have one, ask a pharmacist for one. Do not use a kitchen teaspoon as it will not measure the right amount of medicine.

Ferrous sulfate is not harmful if it's been prescribed for your child and you follow your doctor's instructions, or the instructions on the packet.

How long to take it for

To prevent iron deficiency anaemia, you'll need to take ferrous sulfate for as long as you're at risk of getting this condition.

To treat iron deficiency anaemia, you'll need to take it for several months. Your doctor will usually advise you to keep taking it for 3 to 6 months after your condition has improved to help build up your body's iron supply.

If you forget to take it

If you forget a dose, take it as soon as you remember, unless it's almost time to take the next dose. In this case, skip the missed dose and take your next dose at the usual time.

Do not take 2 doses to make up for a forgotten dose.

If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to remember to take your medicine.

If you take too much

Taking more than the recommended dose of ferrous sulfate can cause vomiting, stomach pain or diarrhoea.

In serious cases you may vomit blood, have a seizure or fit, or become unconscious.

If you go to A&E do not drive yourself. Get someone else to drive you, or call an ambulance.

Take the ferrous sulfate packet or the leaflet inside it and any remaining medicine with you.