Cefotaxime
Drug class: Third-Generation Cephalosporin Antibiotic; beta-lactum antibiotics, specifically categorized as a THIRD-generation cephalosporin.
Cefotaxime (CLAROFAN)（中文：頭孢噻肟）
Common Strengths
Commonly available strengths of cefotaxime include:
- 500 mg
- 1 g
- 2 g
Trade Names
The primary trade name for cefotaxime is Claforan.
Drug Usage
Cefotaxime is indicated for:
- Joint infections
- Pelvic inflammatory disease
- Meningitis
- Pneumonia
- Urinary tract infections
- Sepsis
- Gonorrhea
- Cellulitis
Mechanism of Action
Cefotaxime works by inhibiting bacterial cell wall synthesis. It binds to penicillin-binding proteins (PBPs), blocking the transpeptidation step in peptidoglycan synthesis, leading to bacterial cell lysis and death.
Route of Administration
Cefotaxime is administered via intravenous (IV) or intramuscular (IM) injection.
Dosages
- Uncomplicated infections: 1 g IM or IV every 12 hours.
- Moderate to severe infections: 1 to 2 g IM or IV every 8 hours.
- Life-threatening infections: 2 g IV every 4 hours.
- Renal Dose Adjustments:
- For patients with creatinine clearance (CrCl) less than 20 mL/min, the dose should be reduced by 50%.
Side Effects
| Frequency | Adverse reactions |
|---|---|
| Common Side Effects | Nausea |
| Diarrhea | |
| Injection site reactions (pain, redness, swelling) | |
| Serious Side Effects | Severe allergic reactions (anaphylaxis) |
| Clostridium difficile-associated diarrhea | |
| Hemolytic anemia | |
| Nephrotoxicity, especially when combined with other nephrotoxic agents |
Pharmacokinetics
- The onset of action for cefotaxime typically begins within 30 minutes after IM injection or immediately following IV administration.
- The duration of action is influenced by the half-life (approximately 1 hour); due to its relatively short half-life, cefotaxime is often administered every 6 to 12 hours depending on the infection being treated and patient response. For example:
- In uncomplicated infections, treatment may last around 7 days.
- In more complicated cases, such as meningitis or severe infections, therapy could extend to 10-14 days.
In summary, cefotaxime has a quick onset of action and a short duration of effect, necessitating frequent dosing to maintain effective serum concentrations for therapeutic efficacy against bacterial infections.
Drug Precautions
Pregnancy
Category B; generally considered safe, but benefits must be weighed against risks.
Breastfeeding
Excreted in breast milk; caution is advised.
Children and Elderly
Generally safe, but dosage adjustments may be necessary for renal function.
Monitoring Items
Renal function, liver enzymes, and signs of allergic reactions should be monitored during treatment.
Drug Interactions
Notable interactions include:
- Increased risk of bleeding: When used with anticoagulants like warfarin, careful monitoring of coagulation parameters is necessary.
- Increased nephrotoxicity with aminoglycosides.
- Hormonal contraceptives: Cefotaxime may reduce the effectiveness of hormonal contraceptives, necessitating alternative contraceptive methods during treatment.
- Probenecid can increase cefotaxime levels.
FAQ
How Should I Take the cefaclor?
Cefotaxime is typically administered by injection.
What Should I Avoid While Taking?
Avoid combining cefotaxime with other nephrotoxic drugs unless monitored closely.
What Happens if I Miss a Dose?
If a dose is missed, take it as soon as remembered. If it is almost time for the next dose, skip the missed dose and continue with the regular schedule.
