Which ferrous sulfate (iron) brands are most widely used and cost‑effective in the United States, United Kingdom, Canada, and Australia?

Best Ferrous Sulfate Brands for Iron Deficiency

Generic ferrous sulfate 200 mg tablets (providing 65 mg elemental iron) are the optimal choice regardless of brand, as no manufacturer has demonstrated superior efficacy or tolerability—select the least expensive option available at your local pharmacy. 1

Why Brand Does Not Matter

• All ferrous sulfate formulations contain the same active ingredient and deliver equivalent elemental iron content (approximately 65 mg per 200 mg tablet), making them therapeutically interchangeable. 1, 2
• No clinical trial has ever shown one ferrous sulfate brand to be more effective or better tolerated than another—the chemical compound is identical across manufacturers. 1, 3
• Ferrous sulfate remains the gold standard for oral iron therapy based on decades of clinical evidence, not on any specific brand name. 4, 5

Cost-Effectiveness Across Markets

• In the United Kingdom, generic ferrous sulfate costs approximately £1.00 for a 28-day supply, making it the most economical option. 1
• In the United States, generic ferrous sulfate ranges from $0.30 to $4.50 for 30 tablets, with the lowest-cost generic versions providing identical efficacy to premium brands. 1
• Over-the-counter generic ferrous sulfate purchased at supermarkets or pharmacies is as effective as prescription formulations and typically costs less. 1

What to Look For (Not Brand Names)

• Standard-release tablets only—avoid any product labeled "modified-release," "sustained-release," or "enteric-coated," as these release iron beyond the duodenum and markedly reduce absorption. 1, 2, 6
• 200–325 mg ferrous sulfate per tablet (delivering 65–105 mg elemental iron)—this is the standard therapeutic dose. 1, 6
• Avoid combination products containing ferrous sulfate plus folic acid or ascorbic acid unless you have documented folate deficiency or need vitamin C to enhance absorption when taking iron with food. 1
• Avoid multivitamin preparations as your sole iron source—they contain ≤14 mg elemental iron, which is insufficient for treating iron deficiency. 1, 2

Optimal Dosing Strategy (Same for All Brands)

• Take one tablet (65 mg elemental iron) once daily in the morning on an empty stomach, 1–2 hours before meals, to maximize absorption and minimize gastrointestinal side effects. 2, 3, 6
• Do not take multiple doses per day—a single dose ≥60 mg elemental iron triggers hepcidin elevation for 24 hours, blocking absorption of subsequent doses by 35–45%. 2, 6
• If daily dosing causes intolerable gastrointestinal symptoms, switch to alternate-day dosing (every other day) with 100–200 mg elemental iron, which markedly improves fractional absorption and reduces side effects. 2, 3

When Generic Ferrous Sulfate Is Not Tolerated

• Ferrous fumarate (210–325 mg tablets delivering 69–106 mg elemental iron) or ferrous gluconate (300 mg tablets delivering 37 mg elemental iron) are acceptable alternatives, but evidence does not show improved tolerability compared with ferrous sulfate. 1, 2, 3
• Ferric maltol (30 mg twice daily) may be considered for patients with documented intolerance to all ferrous salts, especially those with inactive inflammatory bowel disease, but it costs approximately £47.60 versus £1.00 for ferrous sulfate per 28 days and produces slower iron loading. 1, 2

Monitoring Response (Same for All Brands)

• Check hemoglobin 2 weeks after starting therapy—an increase of ≥10 g/L predicts treatment success with 90% sensitivity and 79% specificity. 1, 2, 3
• Failure to achieve this rise strongly predicts treatment failure and warrants evaluation for non-adherence, ongoing blood loss, malabsorption, or concurrent vitamin B12/folate deficiency. 1, 2
• After hemoglobin normalizes, continue therapy for an additional 3 months to fully replenish iron stores. 2, 3

Common Pitfalls to Avoid

• Do not pay premium prices for branded ferrous sulfate—generic versions are chemically identical and equally effective. 1
• Do not switch between ferrous sulfate brands expecting better tolerability—the active ingredient is the same, and side effects are dose-dependent, not brand-dependent. 2, 3
• Do not purchase liquid formulations unless tablets cannot be swallowed—they cost significantly more (£60.00 per 28 days for drops versus £1.00 for tablets) without offering therapeutic advantages. 1