Characteristics and side effects of most commonly available oral iron supplements
| Iron formulation (example US brand names) (dose per tablet/Fe dose) . | Usual dose . | Most common side effects (>1%) . | Observations . |
|---|---|---|---|
| Ferric citrate (Auryxia) (1000 mg/210 mg Fe) | 2 tablets once daily (LR) | >20%: fecal discoloration, diarrhea; 10-20%: constipation, nausea; 1-10%: hyperkalemia, cough. | Phosphate binder, approved for use in ID in ndCKD. |
| Ferrous fumarate (Ferretts, Ferrimin, Hemocyte) (324 or 325 mg/106 mg Fe) | 1 tablet every other day (>100 mg Fe per dose) | >10%: constipation, fecal discoloration, nausea, stomach cramps, vomiting; 1-10%: dental discoloration, diarrhea, urine discoloration | Cereals, dietary fiber, tea, coffee, eggs, and milk may decrease absorption. |
| Ferrous gluconate (Ferate) (240 mg/27 mg Fe; 324 mg/38 mg Fe) | 3-4 tablets every other day (>100 mg Fe per dose) | >10%: constipation, fecal discoloration, nausea, stomach cramps, vomiting; 1-10%: dental discoloration, diarrhea, urine discoloration. | |
| Polysaccharide iron complex (EZFE, Ferrex, NovaFerrum) (50 mg Fe) | 2 tablets every other day (>100 mg Fe per dose) | >10%: constipation, fecal discoloration, nausea, stomach cramps, vomiting; 1-10%: dental discoloration, diarrhea, urine discoloration. | |
| Ferrous sulfate (several) (324 or 325 mg/65 mg Fe) | 2 tablets every other day (>100 mg Fe) | >50%: fecal discoloration, abdominal pain, nausea; 20-50%: constipation, vomiting, diarrhea. | |
| Ferric polymaltose (Maltofer; not available in the US) (357 or 370 mg/100 mg Fe) | 1-3 tablets once daily (LR) | >10%: fecal discoloration; >1%: diarrhea, nausea, abdominal pain, constipation. | — |
| Heme iron polypeptide (Proferrin) (10.5-12 mg Fe) | 1 tablet once daily (LR) | Incidence unknown: constipation, abdominal pain, diarrhea, muscle cramps. | — |
| Ferric maltol (Accrufer) (30 mg Fe) | 1 tablet twice daily (LR) | 1-10%: fecal discoloration, constipation, diarrhea, abdominal pain, nausea, vomiting. | Absorption may be decreased with food. |
| Iron formulation (example US brand names) (dose per tablet/Fe dose) . | Usual dose . | Most common side effects (>1%) . | Observations . |
|---|---|---|---|
| Ferric citrate (Auryxia) (1000 mg/210 mg Fe) | 2 tablets once daily (LR) | >20%: fecal discoloration, diarrhea; 10-20%: constipation, nausea; 1-10%: hyperkalemia, cough. | Phosphate binder, approved for use in ID in ndCKD. |
| Ferrous fumarate (Ferretts, Ferrimin, Hemocyte) (324 or 325 mg/106 mg Fe) | 1 tablet every other day (>100 mg Fe per dose) | >10%: constipation, fecal discoloration, nausea, stomach cramps, vomiting; 1-10%: dental discoloration, diarrhea, urine discoloration | Cereals, dietary fiber, tea, coffee, eggs, and milk may decrease absorption. |
| Ferrous gluconate (Ferate) (240 mg/27 mg Fe; 324 mg/38 mg Fe) | 3-4 tablets every other day (>100 mg Fe per dose) | >10%: constipation, fecal discoloration, nausea, stomach cramps, vomiting; 1-10%: dental discoloration, diarrhea, urine discoloration. | |
| Polysaccharide iron complex (EZFE, Ferrex, NovaFerrum) (50 mg Fe) | 2 tablets every other day (>100 mg Fe per dose) | >10%: constipation, fecal discoloration, nausea, stomach cramps, vomiting; 1-10%: dental discoloration, diarrhea, urine discoloration. | |
| Ferrous sulfate (several) (324 or 325 mg/65 mg Fe) | 2 tablets every other day (>100 mg Fe) | >50%: fecal discoloration, abdominal pain, nausea; 20-50%: constipation, vomiting, diarrhea. | |
| Ferric polymaltose (Maltofer; not available in the US) (357 or 370 mg/100 mg Fe) | 1-3 tablets once daily (LR) | >10%: fecal discoloration; >1%: diarrhea, nausea, abdominal pain, constipation. | — |
| Heme iron polypeptide (Proferrin) (10.5-12 mg Fe) | 1 tablet once daily (LR) | Incidence unknown: constipation, abdominal pain, diarrhea, muscle cramps. | — |
| Ferric maltol (Accrufer) (30 mg Fe) | 1 tablet twice daily (LR) | 1-10%: fecal discoloration, constipation, diarrhea, abdominal pain, nausea, vomiting. | Absorption may be decreased with food. |
Fe, elemental iron; LR, label recommendation.