Introduce

Cefdinir, also known as cefdinir in Chinese, is a third-generation cephalosporin antibiotic primarily used to treat various infections caused by sensitive bacteria.

Figure 1 Characteristics of  Cefdinir

Nature

Cefdinir is a white to slightly yellow crystalline powder with no or slight odor. Melting point 170 ℃ (decomposition). pK。9.70。 Semi-synthetic third-generation cephalosporins. White crystalline powder. Slightly soluble in phosphate buffer solution and dilute hydrochloric acid, almost insoluble in general organic solvents such as water, methanol, ethanol, acetone, etc., with no obvious melting point.

Preparation

The preparation of Cefdinir requires using 7-ACA as the raw material, protecting the 7-amino and 2-carboxyl groups, and then reacting with triphenylphosphine to obtain phosphides. It reacts with formaldehyde under alkaline conditions to obtain vinyl derivatives at position 3. Treat it with hydrochloric acid to obtain a compound. The compound reacted with 4-bromoacetyl bromide in ethyl acetate in the presence of N-methylsilylacetamide to obtain an acylation product. Add the obtained acylation product to dichloromethane and acetic acid, nitrosate with sodium nitrite aqueous solution, and then add urea to destroy excess sodium nitrite to obtain hydroxylamine compound. The hydroxylamine compound reacts with thiourea in N, N-methylacetamide to obtain a crude compound. The crude compound is reacted with trifluoroacetic acid in benzyl ether and recrystallized to obtain Cefdinir.

Quality standard

Cefdinir, according to the 2005 edition of the Chinese Pharmacopoeia, should contain no less than 94% cefdinir (C14 H-Ns Os S2) when calculated as anhydrous 0%. The pH value should be between 2.5 and 4.5. The moisture content shall not exceed 2.0%; Burning residue shall not exceed 0.2%. The content of heavy metals shall not exceed 0.001%.

Purpose

Developed by Fujisawa Pharmaceutical Industry Co., Ltd. in Japan, it was launched in October 1991. In December 1997, Cefdinir was certified by the US FDA and launched in the United States under the trade name Omnicef. Cefdinir is a structurally modified version of cefixime, which compensates for the weak effect of third-generation cephalosporins on Gram-positive bacteria. It has excellent antibacterial activity against both Gram-positive and Gram-negative bacteria. Used for infectious pustules, erysipelas, subcutaneous abscesses, mastitis, surface infections after trauma and surgery, pharyngitis, acute bronchitis, pneumonia, tonsillitis, urethritis, intrauterine infections, etc.

Usage and dosage

The standard dose of Cefdinir for adults is 3 times a day, 2 bags per dose (100mg potency). The standard dosage for children is 9-18mg (potency)/kg per day, taken orally in 3 doses of 5.

Adverse reactions

Cefdinir may cause some side effects such as diarrhea, nausea, vomiting, and rash, but these side effects are usually mild and temporary. If serious side effects or allergic reactions occur during use, stop using immediately and consult a doctor. Common adverse reactions include allergic rash, urticaria, itching, fever, edema, and erythema.

Security

In terms of safety, the overall incidence of adverse reactions to Cefdinir is 3.4%, with gastrointestinal reactions such as soft stools, diarrhea, stomach discomfort, nausea, loss of appetite, belching, etc. being more common and mild in severity. Allergic reactions such as rash and itching account for only 0.8%. The proportion of patients with elevated serum aminotransferase is 0.3%. Other conditions include erythema multiforme, joint pain, arthritis, etc. Serum-like reactions are more common than other oral antibiotics, especially in pediatric patients, with typical symptoms including skin reactions and joint pain. About 1% of patients discontinue medication due to adverse reactions.

The adverse reactions of Cefdinir are mild and mostly self-limiting. The common adverse reactions are mainly gastrointestinal reactions such as diarrhea, abdominal pain, stomach discomfort, heartburn, nausea, and allergic reactions such as rash and itching. Common adverse events include vaginal candidiasis, nausea, headache, etc. Less common adverse reactions include rash, indigestion, bloating, vomiting, and dizziness. Common laboratory abnormalities include elevated levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and eosinophilia.

Reference

[1] Perry C M, Scott L J. Cefdinir: a review of its use in the management of mild-to-moderate bacterial infections[J]. Drugs, 2004, 64(13): 1433-1464.

[2] Guay D R P. Cefdinir: an expanded-spectrum oral cephalosporin[J]. Annals of Pharmacotherapy, 2000, 34(12): 1469-1477.