Iron Pills for Heavy Periods: 5 Checks Before You Start Taking Them

In the years before menopause, periods can get heavier, longer or closer together. Losing more blood each month can lower your iron, and tiredness and shortness of breath can follow. Iron supplements are cheap and easy to grab, which is exactly why a few checks matter before you start.

1. Get the blood test first

The NIH’s Office of Dietary Supplements says most people in the U.S. get enough iron, but women with heavy periods are among the groups more likely to fall short.¹ The NHS² lists heavy periods as a common cause of iron deficiency anemia, along with bleeding in the stomach and intestines. A full blood count is the usual first test.²

A test tells you whether you’re low and how low, and it gives you a starting number to compare against later. The NIH also notes that iron can be harmful if you take too much.¹ Ask for a blood test before you add a supplement, not after.

2. Ask why you’re losing iron

Iron pills replace what’s lost. They don’t stop the bleeding. The NHS² says a doctor may run more tests to find the cause.² If your periods have become very heavy, ask about the reasons and the treatments for the bleeding itself. If you no longer have periods, or your bowel habits have changed, low iron needs a look at your stomach and bowel, which the NHS lists as another source of blood loss.²

3. Check your other medicines

The NIH lists several interactions:¹

• Levothyroxine for an underactive thyroid. Iron taken with it can make it less effective.
• Levodopa, used for Parkinson’s disease and restless legs. Iron can reduce how much you absorb.
• Acid reducers such as omeprazole and lansoprazole may reduce how much iron you absorb from food.
• Calcium may interfere with iron absorption. The NIH suggests taking calcium and iron at different times of day.

Ask your pharmacist how to space iron from your thyroid pill and calcium, and write the schedule down.

4. Pick a dose with your clinician, not the shelf

Iron in supplements often comes as ferrous sulfate, ferrous gluconate, ferric citrate or ferric sulfate.¹ Doses vary a lot from bottle to bottle. The NIH sets the upper limit for adults at 45 mg a day, though doctors sometimes prescribe more for a while to treat a deficiency.¹

High doses, especially on an empty stomach, can cause upset stomach, constipation, nausea, abdominal pain and diarrhea.¹ The NHS² notes that taking iron with food may reduce side effects, and that dark stools are expected. Tea, coffee and dairy can make iron harder to absorb.² The NIH notes that vitamin C helps your body absorb iron from plant foods.¹

The NHS² says treatment usually lasts about six months.² Ask when your blood should be rechecked.

5. Lock it away from grandchildren

Iron supplements carry a warning to keep them out of reach of children. Accidental iron overdose is a leading cause of fatal poisoning in children under 6.¹ Keep the bottle in a locked or high cabinet, not in a purse or on the kitchen counter, especially when grandchildren visit.

Try: “My periods have been much heavier and I feel worn out. Can we check my iron and talk about what’s causing the bleeding?”

Period, Handled includes a Period Scorecard and a visit script. Use them to record how heavy your periods are and how you’ve been feeling, so the visit covers both the iron and the bleeding. See the book.