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Iron supplement constipation?

My girlfriend just started taking iron supplements, 65mg once a day. Approximately how many days does it take for the side effect of constipation to kick in? If it does should she take a stool softener each day or is an enema a good option?





Female | 69 years old
Medications: IRON 65MG

5 Answers

Side effects to oral iron, like all meds, are variable. They may not occur at all, or will start immediately, or may take time to develop. If she gets constipation, then it is reasonable to increase fiber and use laxatives (e.g., dulcolax, miralax, laxative tea, etc.) as needed. My personal opinion is that stool softeners are not very effective since they do not act as purgatives or stimulants to induce bowel movements.
Constipation form iron supplements can occur in a few days. Stool softeners should be fine to take. Another thing I would advise is to make sure the cause of iron deficiency has been determined( there is almost always a reson to become iron deficient- slow bleeding, low dietary intake, lack of absorption of iron , blood donation and GI, menstrual or urinary tract bleeding to name a few).
Many iron supplements cause constipation which can be avoided by using stool softeners at the same time.
There is no guarantee that iron supplementation will cause constipation nor should it be used to try and induced constipation. If you are concerned about preventing constipation from occurring, use an iron supplement that is derived from beets Instead. As always, one way to ensure a good colonic health and regular bowel movements is to eat foods rich in fiber trying to get 30 g of fiber per day. An easy way to do this as long as you are not gluten intolerant is 1/3 of a cup of Kelloggs all bran bran buds every day. Mix this with chocolate milk and it’s almost like eating dessert. Finally, rather than taking a stool softener, you’re always better to change the iron preparation to one that doesn’t constipate.


Iron tablets are likely to alter bowel movements, yes. It is well known. Yes. To reduce constipation with iron, take each tablet with additional vitamin C. A 500 mg tablet with the iron tablet will enhance the intestinal absorption of iron. Also, drink a minimum of 6-8 ounces of fruit juice with the iron tablet and vitamin C. This enhances absorption and disperses the iron compound. And repeat the glass of fruit juice twice more. And eat more food fiber such as an apple, a pear, a peach, or high-fiber oatmeal each day is important. And yes, a daily regular capsule of Senna plus Colace is important and essential.