Ferrous Sulfate
Ferrous sulfate is an iron supplement used to treat or prevent iron deficiency anemia, a condition where the body lacks enough healthy red blood cells due to low iron levels. It is commonly prescribed for individuals with anemia caused by pregnancy, poor diet, blood loss, or certain medical conditions that impair iron absorption.
Ferrous sulfate is an oral iron supplement that treats iron deficiency anemia by replenishing iron stores in the body.
Key facts at a glance
- ATC
- B03AA07
- RxNorm
- 24967
- Generic
- Ferrous Sulfate
- Class
- atc-b03
- Brands
- Slow-Fe, Feosol, Fer-in-Sol, Folitab
- Availability
- otc
- Pregnancy
- A
- Lactation
- safe
- Half-life (h)
- 0
- Onset (min)
- 0
- Duration (h)
- 0
- Routes
- oral, topical
- Forms
- tablet, extended-release tablet, capsule, oral solution, drops, elixir, syrup
- Regions
- United States, Canada, United Kingdom, European Union, Australia, India, China, Brazil, Japan
- Monitoring
- hemoglobin, hematocrit, serum ferritin, transferrin saturation, reticulocyte count
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
first trimesteruse only if iron deficiency confirmed
avoid unnecessary supplementation, only use when benefits outweigh risks
regular prenatal checkups and hemoglobin monitoring
Use with caution and monitor for adverse effects.
pregnancy
second trimesterstandard adult dosing
commonly prescribed for iron deficiency anemia in pregnancy
routine hemoglobin and hematocrit checks
pregnancy
third trimesterstandard adult dosing
important for maternal iron stores and fetal iron储备
monitor iron studies and hemoglobin
lactation
breastfeedingstandard adult dosing
compatible with breastfeeding, iron is secreted in minimal amounts in breast milk
maternal hemoglobin monitoring
pediatric_age
children 2 12 yearsweight-based dosing required
use pediatric formulations, keep out of reach of children to prevent overdose
close supervision of dosing, monitor for toxicity
Use with caution and monitor for adverse effects.
geriatric
elderly 65 yearsstart with lower dose
may need lower doses due to decreased GI tolerance, consider alternative formulations
monitor for GI side effects and hemoglobin response
Use with caution and monitor for adverse effects.
renal_impairment
mild to moderatemay require dose adjustment
patients on dialysis may require higher doses due to blood loss
regular monitoring of iron studies and renal function
Use with caution and monitor for adverse effects.
hepatic_impairment
mild to moderateuse with caution
monitor liver function and iron studies
regular monitoring of ferritin and liver enzymes
Use with caution and monitor for adverse effects.
Statistics and clinical data
Commonly prescribed since
General prescribing information for iron deficiency treatment
Drug class
Mineral supplement class information
Common uses
Primary therapeutic indication
Typical elemental iron content
Standard ferrous sulfate composition
Ferrous sulfate is used to treat and prevent iron deficiency anemia, including anemia associated with pregnancy, menstrual blood loss, gastrointestinal bleeding, surgery, dialysis, and inadequate dietary iron intake.
Ferrous sulfate provides elemental iron, which is a key component of hemoglobin—the protein in red blood cells that carries oxygen throughout the body. By replenishing iron stores, it helps restore normal hemoglobin levels and improves oxygen transport in the blood.
Take on an empty stomach with water or juice for best absorption (unless stomach upset occurs, then take with food). Avoid taking with antacids, calcium supplements, or dairy products as they can reduce absorption. Common side effects include constipation, dark stools, nausea, and stomach upset. Store away from children as iron overdose can be dangerous.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 26, 2026. · Read our editorial policy