3847-29-8

White or slightly yellow hygroscopic, powder.

Macrolide antibacterial.

Erythrocin (Abbott); Erythrocin (Hospira).

Erythromycin (Item No. 16486) is a macrolide antibiotic that inhibits bacterial protein synthesis by targeting the 50S ribosomal subunit, blocking the progression of nascent polypeptide chains. It is effective against a host of bacterial genera, including Streptococcus, Staphylococcus, and Haemophilus (MIC₉₀s range from 0.015-2.0 mg/l). Erythromycin is known to potently inhibit the cytochrome P450 isoform CYP3A4, which can affect the metabolism of numerous clinically relevant medications. Erythromycin lactobionate is a soluble salt of erythromycin that is typically used for intraperitoneal or intravenous injections.

Erythrocin,Abbott,US,1954

A solution of erythromycin free base is prepared by dissolving 8.0 grams of erythromycin in 25 cc of acetone. 4.0 grams of lactobiono-delta-lactone is dissolved in 25 cc of water. The free lactobionic acid is formed in this solution and it has the molecular formula C12H22O12. The two solutions are mixed and evaporated to a gummy residue. This residue is dissolved in 60 cc of water and the solution is frozen and dried in vacuum by lyophilization. The dried residue of erythromycin lactobionate is a white amorphous powder and weighs 11.7 grams. The reaction product has an activity against B. subtilis of 420units per milligram. Its solubility in water is about 200 mg/cc and the melting point of the white powdery reaction product is 145° to 150°C.

Antibacterial

Erythromycin lactobionate is a water-soluble salt preparedby reacting erythromycin base with lactobiono-σ-lactone. Itoccurs as an amorphous powder that is freely soluble inwater and alcohol and slightly soluble in ether. It is intended,after reconstitution in sterile water, for intravenousadministration to achieve high plasma levels in the treatmentof serious infections.