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Quiofic
folic acid (vitamin B9)
Adult Dosing .
Dosage forms: SOL: 0.2 mg per mL
Special Note
- [strength clarification]
- Info: doses expressed as folic acid; 1 mg PO folic acid = 1.67 mg Dietary Folate Equivalent (DFE) if taken with food or 2 mg DFE if taken on empty stomach
megaloblastic anemia, folate deficiency-associated
- [0.4 mg PO qd]
- Start: up to 1 mg PO qd until hematologic correction; Info: incr. usual dose to 0.8 mg PO qd in pregnant or breastfeeding patients; consider incr. usual dose if alcoholism, hemolytic anemia, or chronic infection; doses >1 mg/day rarely more effective
dietary supplementation
- [individualize dose]
- Info: see Dietary Reference Intakes: Vitamin B9 (folic acid) table
neural tube defect prevention (off-label)
- [0.4 mg PO qd]
- Start: at least 1mo before conception; Info: for patients of childbearing potential; continue through 12 wk gestation; give 4 mg PO qd if high risk of neural tube defect
renal dosing
- [not defined]
- renal impairment: not defined
- HD/PD: not defined
hepatic dosing
- [not defined]
Peds Dosing .
- Dosage forms: SOL: 0.2 mg per mL
Special Note
- [strength clarification]
- Info: doses expressed as folic acid; 1 mg PO folic acid = 1.67 mg Dietary Folate Equivalent (DFE) if taken with food or 2 mg DFE if taken on empty stomach
megaloblastic anemia, folate deficiency-associated
- [<2 yo]
- Dose: 0.1 mg PO qd; Start: up to 1 mg PO qd until hematologic correction; Info: consider incr. usual dose if alcoholism, hemolytic anemia, or chronic infection; doses >1 mg/day rarely more effective
- [2-3 yo]
- Dose: up to 0.3 mg PO qd; Start: up to 1 mg PO qd until hematologic correction; Info: consider incr. usual dose if alcoholism, hemolytic anemia, or chronic infection; doses >1 mg/day rarely more effective
- [4 yo and older]
- Dose: 0.4 mg PO qd; Start: up to 1 mg PO qd until hematologic correction; Info: consider incr. usual dose if alcoholism, hemolytic anemia, or chronic infection; doses >1 mg/day rarely more effective
dietary supplementation
- [individualize dose]
- Info: see Dietary Reference Intakes: Vitamin B9 (folic acid) table
neural tube defect prevention (off-label)
- [0.4 mg PO qd]
- Start: at least 1mo before conception; Info: for patients of childbearing potential; continue through 12 wk gestation; give 4 mg PO qd if high risk of neural tube defect
renal dosing
- [not defined]
- renal impairment: not defined
- HD/PD: not defined
hepatic dosing
- [not defined]
Contraindications / Cautions .
- hypersensitivity to drug or ingredient
- pernicious anemia, undiagnosed
Drug Interactions .
Overview
folic acid (vitamin B9)
vitamin
- binds to anion exchange resin/polymer
- glucarpidase substrate
Avoid/Use Alternative
- glucarpidase
- pafolacianine
Monitor/Modify Tx
- cholestyramine
- colestipol
- phenytoin
Caution Advised
- capecitabine
- green tea
Adverse Reactions .
Serious Reactions
- hypersensitivity reaction
- bronchospasm
Common Reactions
- anorexia
- nausea
- abdominal pain
- flatulence
- dysgeusia
- altered sleep patterns
- irritability
- overactivity
- confusion
- rash
- pruritus
- vitamin B12 deficiency (long-term use)
Safety/Monitoring .
Monitoring Parameters
no routine tests recommended
Look/Sound-Alike Drug Names
folic acid confused with: folinic acid
Pregnancy/Lactation .
Pregnancy
Clinical Summary
may use during pregnancy; recommended dietary allowance 600 mcg/day during pregnancy, expressed as dietary folate equivalents; no known risk of fetal harm based on human data; risk of fetal harm with folic acid deficiency
Lactation
Clinical Summary
may use while breastfeeding; recommended dietary allowance 500 mcg/day while breastfeeding, expressed as dietary folate equivalents; no known risk of infant harm based on limited human data; no human data available to assess effects on milk production
Pharmacology .
Metabolism: for vitamin B9: liver; CYP450: unknown; Info: active metabolite
Excretion: for vitamin B9: urine primarily, feces minimally; Half-life: unknown
Subclass: Vitamins/Nutritionals
Mechanism of Action
for vitamin B9: participates in DNA synthesis and erythropoiesis
Formulary .
No Formulary Selected
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