Folinic Acid

Folinic Acid is a reduced folate; folate antagonist antidote medicine available in Bangladesh under many brand names. Below are its uses, dosage, side effects and precautions — and all brands with their current prices.

• Leucovorin rescue to reduce harmful effects after high-dose methotrexate therapy.
• Treatment of overdose or severe toxicity from folic acid antagonists such as methotrexate, when directed by a specialist.
• Use with fluorouracil in certain colorectal cancer chemotherapy regimens.
• Treatment of megaloblastic anaemia due to folate deficiency when folinic acid is specifically considered appropriate; vitamin B12 deficiency must be excluded.

Adult dosing of Folinic Acid varies widely depending on the indication, body size, kidney function, methotrexate blood levels, blood counts, and the chemotherapy protocol. It may be given as a tablet or by injection into a vein or muscle as prescribed. For methotrexate rescue, the timing after methotrexate and repeated doses are critical and are usually guided by laboratory monitoring. Do not change the dose, delay doses, or stop treatment without the prescribing doctor’s advice.

• Nausea, vomiting, diarrhoea, mouth soreness, or abdominal discomfort.
• Rash, itching, urticaria, flushing, or fever.
• Rare allergic or anaphylactoid reactions, including breathing difficulty or swelling of the face or throat.
• Rare seizures or fainting, especially in susceptible patients.
• When used with fluorouracil, side effects of fluorouracil may be increased, including severe diarrhoea, mouth ulcers, low blood counts, infection risk, and hand-foot skin reaction.

Use extra caution in patients with kidney impairment, dehydration, fluid accumulation, or delayed methotrexate clearance, as methotrexate toxicity may be prolonged. In anaemia, vitamin B12 deficiency or pernicious anaemia must be ruled out because folinic acid may improve blood findings while allowing nerve damage to progress. Patients with seizure disorders should be monitored because folates may affect some anti-epileptic medicines. Elderly or frail patients and those receiving fluorouracil need close monitoring for severe gastrointestinal toxicity and low blood counts. Use this medicine only under the guidance of a registered doctor or pharmacist.

• Methotrexate and other folate antagonists: Folinic Acid can reduce their toxicity, but incorrect timing may reduce intended anti-cancer effect or fail to prevent toxicity.
• Fluorouracil and related fluoropyrimidines: folinic acid can increase both anti-cancer effect and serious toxicity, especially diarrhoea, mucositis, and bone marrow suppression.
• Anti-epileptic medicines such as phenytoin, phenobarbital, primidone, and some succinimides: folinic acid may reduce their blood levels and increase seizure risk.
• Trimethoprim, pyrimethamine, or trimetrexate: folinic acid may reduce antifolate toxicity but may also affect intended antimicrobial or anticancer activity depending on the regimen.
• No important food interaction is well established, but follow the administration instructions provided with the prescribed product.

• Known hypersensitivity to folinic acid, leucovorin, calcium folinate, or any component of the product.
• Megaloblastic anaemia caused by vitamin B12 deficiency, including pernicious anaemia, if folinic acid is used as the only treatment.
• Intrathecal administration must not be used; folinic acid injection is not for injection into the spinal canal and this route can be fatal.

Folinic Acid itself is a form of folate and may be used in pregnancy or breastfeeding when clearly needed, but its common partner medicines such as methotrexate or fluorouracil can be harmful and may be contraindicated. Pregnant or breastfeeding patients should use it only after specialist assessment of the full treatment regimen and the expected benefits and risks.

Store tablets in a cool, dry place away from light and moisture. Store injections as directed on the product label, usually protected from light and within the recommended temperature range; do not use if the solution is discoloured or contains particles. Keep all medicines out of the reach of children and do not use after the expiry date.