Esmolol is a short-acting, cardioselective beta-1 adrenergic receptor blocker used as an active pharmaceutical ingredient in medicines for the rapid control of heart rate and certain cardiovascular conditions. Its very short duration of action makes it suitable when rapid titration of beta-blockade is required.
Esmolol is commonly supplied pharmaceutically as esmolol hydrochloride, a water-soluble hydrochloride salt used in intravenous formulations.
Esmolol is a synthetic beta-adrenergic blocking agent belonging to the cardioselective beta-1 blocker class. It preferentially blocks beta-1 adrenergic receptors in cardiac tissue and reduces sympathetic stimulation of the heart.
The molecular formula of Esmolol is C₁₆H₂₅NO₄, with a molecular weight of approximately 295.38 g/mol. Esmolol hydrochloride has a molecular weight of approximately 331.84 g/mol.
CAS Number: 103598-03-4 for esmolol; 81147-84-2 for esmolol hydrochloride.
Esmolol competitively blocks beta-1 adrenergic receptors, reducing the effects of catecholamines such as epinephrine and norepinephrine on the heart.
This produces:
Esmolol has an exceptionally short duration of action because it is rapidly metabolized by esterases in red blood cells.
Esmolol is primarily used in pharmaceutical formulations for:
The exact approved indications depend on the applicable regulatory product labeling.
Esmolol is a small-molecule cardiovascular API belonging to the beta-blocker class. Pharmaceutical products are generally formulated using esmolol hydrochloride for intravenous administration.
Quality evaluation may include identity, assay, related substances, water content, residual solvents, optical purity where applicable and other physicochemical parameters.
Pharmaceutical-grade Esmolol/Esmolol Hydrochloride intended for manufacturing should comply with the applicable approved specification and relevant pharmacopoeial and regulatory requirements.
Typical quality-control parameters include:
A qualified supplier should provide Certificate of Analysis (CoA), specification sheet, SDS/MSDS, batch traceability and applicable regulatory documentation.
Esmolol API should be stored in a tightly closed container, protected from excessive moisture, heat and direct light, according to the applicable 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 20 ppm |
| pH (1% Solution) | 2.0 – 4.0 |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 1.0% |