Trimethoprim/polymyxin

Trimethoprim/polymyxin is a combination antibiotic medication used to treat bacterial infections. This combination includes two active ingredients: trimethoprim and polymyxin B.

Mechanism of Action

Trimethoprim works by inhibiting bacterial dihydrofolate reductase, an enzyme involved in the synthesis of tetrahydrofolic acid, which is necessary for the production of bacterial DNA, RNA, and proteins. By blocking this enzyme, trimethoprim effectively halts bacterial growth.

Polymyxin B, on the other hand, is a polypeptide antibiotic that targets the bacterial cell membrane. It binds to the lipopolysaccharides in the outer membrane of Gram-negative bacteria, disrupting the membrane's integrity and causing cell death.

Uses

Trimethoprim/polymyxin is primarily used to treat infections caused by susceptible strains of bacteria. It is often prescribed for:

• Urinary tract infections
• Eye infections
• Skin infections

Side Effects

Common side effects of trimethoprim/polymyxin may include:

• Nausea
• Vomiting
• Diarrhea
• Rash

Serious side effects can include:

• Allergic reactions
• Kidney problems
• Blood disorders

Precautions

Patients with a history of allergy to either trimethoprim or polymyxin B should avoid this medication. It is also important to use this medication under the guidance of a healthcare professional, especially in patients with kidney disease or blood disorders.

Related Pages

• Antibiotic
• Bacterial infection
• Dihydrofolate reductase
• Polypeptide antibiotic
• Gram-negative bacteria