Folix 5mg Tablet 10pcs

✔️ Uses of Folix 5

• Colorectal cancer
• Methotrexate toxicity
• Megaloblastic anaemia

✔️ Pharmacology

Calcium folinate (Folinic Acid) is the calcium salt of tetrahydrofolic acid, a metabolite and active form of folic acid. It serves as a cofactor for 1-carbon transfer reactions in the synthesis of purines and pyrimidines, which are crucial for DNA and RNA production.

Mechanism of Action:

• Calcium folinate enters cells as 5-methyl tetrahydrofolate and supplies the cofactor blocked by methotrexate.
• It stabilizes the binding of 5-dUMP (deoxyuridine monophosphate) to thymidylate synthetase, thereby enhancing the action of fluorouracil (5-FU).
• It neutralizes the effects of folic acid antagonists such as methotrexate by bypassing the blockade of dihydrofolate reductase.

Interaction with 5-FU:

• Calcium folinate enhances the cytotoxicity of 5-fluorouracil (5-FU) by stabilizing the fluorouracil-thymidylate synthetase complex, increasing its efficacy in cancer treatment.

Selective Rescue:

• Calcium folinate preferentially rescues normal cells from the toxic effects of folic acid antagonists, such as methotrexate, while allowing continued activity against tumor cells due to differences in membrane transport and metabolism.

✔️ Dosage & Administration of Folix 5

1. Folinic Acid Rescue:

• Start within 24 hours of methotrexate administration or overdose.
• Administer 15 mg (10 mg/m²) every 6 hours for 10 doses.

2. Neutralizing Toxic Effects (e.g., Methotrexate Overdose):

• Dose of Folinic Acid must be equal to or greater than the methotrexate dose.
• Administer within 1 hour of methotrexate exposure.

3. Megaloblastic Anemia (Folate Deficiency):

• 5 mg to 15 mg daily.

Use in Children:

• Safety and efficacy not established.

✔️ Interactions

• Antiepileptic Drugs: Large doses may reduce the effect of phenobarbital, phenytoin, and primidone, increasing seizure frequency.
• Fluoropyrimidine (e.g., 5-FU): May increase the risk of seizures and syncope during concurrent use.

✔️ Contraindications

• Known hypersensitivity to calcium folinate or its components.
• Pernicious anemia or megaloblastic anemia caused by vitamin B12 deficiency.
• Patients with rare hereditary conditions like:
  • Galactose intolerance.
  • Lapp lactase deficiency.
  • Glucose-galactose malabsorption.

✔️ Side Effects of Folix 5

• Common:
  • Mucositis.
  • Stomatitis.
  • Leukopenia.
  • Diarrhea.

✔️ Pregnancy & Lactation

• Pregnancy: Use only if potential benefits outweigh the risks.
• Lactation: Unknown if excreted in breast milk; caution advised.

✔️ Precautions & Warnings

• Use under medical supervision when combined with methotrexate or 5-FU.
• Begin folinate treatment as soon as possible if folic acid antagonist overdose occurs (delays >4 hours may reduce efficacy).
• Ensure methotrexate excretion with:
  • Urine alkalinization (pH >7.0).
  • Adequate hydration (1800-2000 cc/m²/day).
  • Monitoring of plasma methotrexate levels, BUN, and creatinine.

✔️ Storage Conditions

• Store below 30°C.
• Protect from light and moisture.
• Keep out of reach of children.