1¹⁄₂ years and upward, full dose. From 9 to 18 months old, ¹⁄₂ dose. From 4¹⁄₂ to 9 months, ¹⁄₄ dose. From 2¹⁄₂ to 4¹⁄₄ months, ¹⁄₈ dose. From 1 to 2¹⁄₂ months, ¹⁄₁₆ dose.