Ethambutol Hydrochloride (Ethambutol HCl) is an antimycobacterial active pharmaceutical ingredient (API) used as part of combination therapy for the treatment of tuberculosis (TB). It inhibits the growth of susceptible Mycobacterium species by interfering with the synthesis of components of the mycobacterial cell wall.
Ethambutol HCl is commonly used in combination with other anti-tuberculosis medicines to help prevent the development of drug resistance.
Ethambutol Hydrochloride is the hydrochloride salt of ethambutol, a synthetic antimycobacterial compound. It is generally supplied as a pharmaceutical-grade crystalline material for use in the manufacture of tablets and other approved formulations.
CAS Number: 1070-11-7
Molecular Formula: C₁₀H₂₄Cl₂N₂O₂
Molecular Weight: 277.23 g/mol
Ethambutol inhibits enzymes involved in the biosynthesis of the mycobacterial cell wall, particularly arabinosyl transferases encoded by the embCAB gene complex.
This leads to:
Ethambutol is primarily bacteriostatic at clinically relevant concentrations.
Ethambutol HCl is used as an API in pharmaceutical formulations for:
Ethambutol is generally used as part of a multi-drug regimen, rather than as monotherapy.
Ethambutol HCl is an antimycobacterial API with defined chemical and stereochemical characteristics. Pharmaceutical-grade material requires control of identity, assay, related substances, water content and other applicable quality attributes.
Typical quality evaluation may include:
Pharmaceutical-grade Ethambutol HCl should comply with the applicable pharmacopoeial monograph, approved specification and regulatory requirements.
Because Ethambutol has stereochemical requirements, appropriate control of optical rotation and stereochemical purity is important for pharmaceutical quality.
A qualified supplier should provide Certificate of Analysis (CoA), specification sheet, SDS/MSDS, batch traceability and applicable regulatory documentation.
Store Ethambutol HCl in a tightly closed container, protected from excessive moisture, heat and direct light, according to the manufacturer's approved storage and stability requirements.
| Parameter | Specification |
|---|---|
| Appearance | White to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Heavy Metals | NMT 10 ppm |
| pH (1% Solution) | 2.0 – 4.0 |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 1.0% |
| Water Content | NMT 1.0% |
| Melting Point | 150°C – 154°C |