Restless Legs Syndrome and Related Disorders - Treatment

Supplement Forms. To replace iron, the preferred forms of iron tablets are ferrous salts, usually ferrous sulfate (Feosol, Fer-In-Sol, Mol-Iron). Other forms include ferrous fumarate (Femiron, FerroSequels, Feostat, Fumerin, Hemocyte, Ircon), ferrous gluconate (Fergon, Ferralet, Simron), polysaccharide-iron complex (Niferex, Nu-Iron), and carbonyl iron (Elemental Iron, Feosol Caplet, Ferra-Cap). Specific brands and forms may have certain advantages. The following are some examples:

Prolonged-release ferrous sulfate (Slow Fe) may enhance iron absorption with fewer side effects than standard ferrous sulfate pills.
FerroSequels contains a stool softener, which helps prevent constipation.
Polysaccharide-iron complex has fewer side effects and equal absorption rates compared to ferrous salts. It is very expensive, however.
Carbonyl iron is composed of very fine tiny uniform spheres of iron powder and may prove to be less toxic than ferrous iron.
Coated or combination pills do not appear to offer any additional advantages and may hinder absorption of the iron.

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Regimen. A reasonable approach for patients with RLS is to take 65 mg of iron (or 325 mg of ferrous sulfate) along with 100 mg of vitamin C on an empty stomach three times a day.

IMPORTANT: As few as three adult iron tablets can poison, and even kill,children. This includes any form of iron pill. No one, even adults, should take a double dose of iron if one is missed.

Tips for taking iron are as follows:

For best absorption, iron should be taken between meals. (Iron may cause stomach and intestinal disturbances, however, and some experts believe that low doses of ferrous sulfate can be taken with food and absorbed without side effects.)
One should always drink a full eight ounces of fluid with an iron pill.
Tablets should be kept in a cool place. (Bathroom medicine cabinets may be too warm and humid, which may cause the pills to disintegrate.)
One study suggested that iron supplements impeded the absorption of non-heme iron (found in legumes and other vegetables) but not heme iron (contained in meat).

Side Effects. Common side effects of iron supplements include the following:

Constipation and diarrhea are very common. They are rarely severe, although iron tablets can aggravate existing gastrointestinal problems such as ulcers and ulcerative colitis.
Nausea and vomiting may occur with high doses, but can be controlled by taking smaller amounts. Switching to ferrous gluconate may help some people with severe gastrointestinal problems.
Black stools are normal when taking iron tablets. In fact, if they do not turn black, the tablets may not be working effectively. This tends to be a more common problem with coated or long-acting iron tablets.
If the stools are tarry looking as well as black, if they have red streaks, or if cramps, sharp pains, or soreness in the stomach occur, gastrointestinal bleeding may be causing the iron deficiency and the patient should call the doctor promptly.
Acute iron poisoning is rare in adults, but can be fatal in children who take adult-strength tablets.