摘要 |
<p>An injectable, aqueous pharmaceutical composition for the treatment of cardiac conditions comprising an effective amount of methyl 3-[4-(2-hydroxy-3-isopropylamino)propoxy]phenylpropionate hydrochloride (esmolol) for treating such a cardiac condition, said composition comprising about 1 mg to 250 mg of esmolol per milliliter of said injectable pharmaceutical composition; 0.01 to 0.20 M buffer; said composition having a pH range of 4.5 to 5.5, the esmolol degrading in aqueous solution to produce 3-[4-(3-propionic acid)-phenoxy]-1-isopropylamino-2-propanol hydrochloride, said 3-[4-(3-propionic acid)-phenoxy]-1-isopropylamino-2-propanol hydrochloride having a pK in the pH range of said composition to thereby act as a secondary buffer to increase the buffer capacity and minimize the change in pH as degradation occurs, whereby the stability of esmolol in an aqueous composition is enhanced.</p> |