Methenamine, also known as hexamethylenetetramine or methenamine, is a synthetic heterocyclic compound used primarily as a urinary antiseptic in pharmaceutical formulations. It is also known as hexamine and urotropine.
Methenamine is used for the prevention and suppression of recurrent urinary tract infections in appropriately selected patients. In acidic urine, methenamine decomposes to release formaldehyde, which provides nonspecific antibacterial activity within the urinary tract.
Methenamine has the molecular formula C6H12N4 and a molecular weight of 140.19 g/mol. Its CAS Number is 100-97-0.
It is a white crystalline powder or colorless crystalline material and is freely soluble in water. Methenamine has a cage-like molecular structure consisting of carbon and nitrogen atoms.
Methenamine is converted in acidic urine into formaldehyde, which has nonspecific antibacterial activity. The released formaldehyde acts locally in the urinary tract and interferes with bacterial cellular components.
Methenamine requires sufficiently acidic urinary conditions for effective conversion and therefore its activity depends substantially on urinary pH.
Methenamine is primarily used in pharmaceutical preparations for:
Methenamine is not generally intended for treatment of acute systemic infections and its use should follow the approved product indication.
Methenamine API can be evaluated using validated analytical procedures for identification, assay, related substances, water content, residue on ignition, residual solvents and elemental impurities, as applicable.
Chromatographic, titrimetric and spectroscopic methods may be used for identity, assay and impurity testing. Final acceptance criteria should be based on the manufacturer's validated drug-substance specification and current Certificate of Analysis.
Methenamine should be stored in a tightly closed pharmaceutical-grade container in a cool, dry environment and protected from excessive heat, moisture and incompatible acidic conditions.
Specific storage and transportation requirements should follow the manufacturer's approved specification.
Methenamine API may be supplied for qualified pharmaceutical manufacturing, urinary antiseptic formulation development, analytical testing and research applications, subject to applicable quality and regulatory requirements.
Methenamine is a specialized pharmaceutical API used in urinary antiseptic formulations. Product specifications, Certificate of Analysis, analytical documentation, packaging information and commercial details can be provided according to applicable pharmaceutical requirements.
| Parameter | Specification |
|---|---|
| Appearance | White crystalline powder or crystals |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| pH (1% Solution) | 7.0–9.0 |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 1.0% |
| Water Content | NMT 1.0% |