A fixed-dose combination product containing a low-dose thyroid hormone (Thyroxine) with two B-vitamins (Nicotinamide and Pyridoxine). It is primarily used as a metabolic enhancer and for the supportive treatment of hypothyroidism, particularly in cases associated with nutritional deficiencies or subclinical presentations. The combination aims to address both the endocrine deficiency and potential cofactor deficiencies that may impair energy metabolism.
Adult: One tablet daily, preferably on an empty stomach, 30-60 minutes before breakfast. Dose must be individualized based on clinical response and TSH levels.
Note: Take with a full glass of water on an empty stomach, at least 30-60 minutes before food, coffee, or other medications (especially calcium, iron, antacids) to ensure optimal absorption of thyroxine. Consistency in timing is crucial.
Thyroxine (T4) is a prohormone converted to the active Triiodothyronine (T3) in peripheral tissues. It binds to nuclear thyroid hormone receptors, regulating gene expression to increase basal metabolic rate, protein synthesis, and growth/development. Nicotinamide is a precursor to NAD+ and NADP+, coenzymes critical for redox reactions and cellular energy production (glycolysis, TCA cycle). Pyridoxine (B6) is converted to Pyridoxal Phosphate (PLP), a cofactor for over 100 enzymes involved in amino acid, neurotransmitter, and hemoglobin synthesis.
Pregnancy: Pregnancy Category A for Thyroxine (when used for replacement). However, this combination is not preferred. Thyroid requirements increase by 20-50% during pregnancy, necessitating separate monitoring and dosing of thyroxine. Vitamin needs also change. Use only if clearly needed and under strict supervision with frequent TSH monitoring.
Driving: Usually no effect. However, if symptoms of hyperthyroidism (nervousness, tremor) or dizziness occur, patients should avoid driving or operating machinery.
| Calcium Carbonate / Iron Supplements / Antacids | Markedly decrease absorption of Thyroxine | Major |
| Warfarin | Thyroxine may potentiate anticoagulant effect, increasing INR risk | Major |
| Oral Hypoglycemics / Insulin | Thyroxine may alter glycemic control, requiring dose adjustment | Moderate |
| Phenytoin, Carbamazepine, Rifampicin | Increase hepatic metabolism of Thyroxine, reducing its efficacy | Moderate |
| Amitriptyline, SSRIs | Enhanced effects of both drugs; increased risk of arrhythmias | Moderate |
| Digoxin | Thyroxine may decrease serum digoxin levels | Moderate |
| Ketamine | Risk of severe hypertension and tachycardia | Major |
| Levodopa | Pyridoxine may decrease the efficacy of Levodopa (not Carbidopa/Levodopa combinations) | Moderate |
Same composition (Nicotinamide (20mg) + Thyroxine (15mg) + Vitamin B6 (Pyridoxine) (2mg)), different brands: