calcium folinate hydrate: clinical use

Prescribing considerations

• Coordinate rescue with the relevant methotrexate protocol and avoid delay.
• Assess renal function, hydration, gastrointestinal absorption and third-space fluid collections when methotrexate elimination is delayed.
• Do not use folinic acid simply to treat macrocytosis caused by cytotoxic medicines.
• Consider sodium exposure from injections and lactose-related suitability of the selected tablet.

Contraindications and cautions

• Hypersensitivity to calcium folinate or an excipient.
• Pernicious anaemia or another megaloblastic anaemia caused by vitamin B12 deficiency.
• Intrathecal administration.

Monitoring

• During methotrexate rescue: methotrexate concentration, renal function, urine pH, clinical toxicity and fluid status.
• With fluorouracil: blood count, electrolytes, liver function, diarrhoea, mucositis, dehydration and infection.
• With enzyme-inducing antiseizure medicines: seizure control and, where appropriate, medicine concentrations.
• Confirm vitamin B12 status before treating unexplained megaloblastic anaemia.

Clinical pharmacology

Calcium folinate is racemic folinic acid. Its active reduced-folate component bypasses folate-antagonist blockade and replenishes cellular folate cofactors. It also enhances fluorouracil-mediated thymidylate-synthase inhibition. Oral absorption is saturable; injections provide parenteral exposure.

Formulation and product differences

• Tablets are oral; their score assists swallowing rather than equal subdivision, and the selected tablet contains lactose.
• Injection solutions are for intravenous or intramuscular use only and contain sodium.
• Dilution compatibility, storage and single-use requirements are product-specific.
• Use a parenteral formulation when oral absorption is unreliable.

Tablet

Route: Oral

Strengths: 15 mg

Injection

Route: Parenteral

Strengths: 10 mg/mL