1. Pharmacology
Cefixime Trihydrate is an oral cephalosporin antibiotic that works by inhibiting bacterial cell wall synthesis, which leads to cell lysis and the destruction of the bacteria. It exhibits bactericidal activity against a broad spectrum of both gram-positive and gram-negative bacteria. Cefixime is stable against beta-lactamases produced by some organisms and is absorbed from the gastrointestinal tract after oral administration.
2. Indications
Cefixime Trihydrate is used for the treatment of the following infections:
Upper respiratory infections (e.g., pharyngitis, tonsillitis, otitis media)
Lower respiratory tract infections (e.g., bronchitis, pneumonia)
Urinary tract infections (e.g., cystitis, pyelonephritis)
Gonorrhea (uncomplicated)
Bacterial diarrheal infections
Ear infections (otitis media)
Sinusitis
3. Dosage & Administration
Adults and Children over 12 years:
Standard Dose: 400 mg once daily or 200 mg every 12 hours for 7 to 14 days.
Children (6 months to 12 years):
8 mg/kg/day in one or two divided doses.
The drug should be taken with food to minimize gastrointestinal upset.
Note: Dosage may vary depending on the severity of the infection, renal function, and specific patient factors.
4. Interactions
Probenecid: Increases the blood concentration of cefixime by reducing its renal excretion.
Antacids: Can decrease the absorption of cefixime.
Warfarin: Antibiotics like cefixime can alter the bacterial flora in the gut, affecting vitamin K production and potentially enhancing the effects of warfarin.
Other antibiotics: When used in combination, the effects may be synergistic or antagonistic, depending on the bacteria involved.
5. Contraindications
Hypersensitivity: Contraindicated in patients with a history of severe allergic reactions (e.g., anaphylaxis) to cephalosporins.
Renal impairment: Dosage adjustments may be required in patients with severe renal impairment.
Liver disease: Caution should be taken in patients with liver dysfunction.
Penicillin allergy: Although there is a low cross-reactivity, patients with a known allergy to penicillin may have a higher risk for reactions.
6. Side Effects
Common side effects include:
Gastrointestinal disturbances (e.g., diarrhea, nausea, vomiting, abdominal pain)
Rash
Headache
Dizziness
Liver enzyme abnormalities
Elevated creatinine levels
Severe reactions (though rare) may include:
Anaphylaxis
Seizures (in case of renal impairment or overdose)
Blood dyscrasias (e.g., neutropenia, thrombocytopenia)
7. Pregnancy & Lactation
Pregnancy: Category B. There is no evidence of harm to the fetus in animal studies, but cefixime should be used during pregnancy only if clearly needed and after careful consideration of the risks and benefits.
Lactation: Cefixime is excreted in breast milk in small amounts. It should be used with caution in nursing mothers, especially in newborns.
8. Precautions & Warnings
Renal impairment: Caution is required in patients with impaired renal function. Dose adjustment may be necessary.
Gastrointestinal disease: Use with caution in patients with a history of gastrointestinal disease, particularly colitis.
Superinfection: Prolonged use may result in overgrowth of non-susceptible organisms (e.g., Candida, Clostridium difficile).
Allergic reactions: Cephalosporins can cause allergic reactions, including severe anaphylactic reactions.
9. Overdose Effects
Symptoms of overdose may include:
Nausea
Vomiting
Diarrhea
Seizures (especially in patients with impaired renal function)
In case of overdose, treatment should focus on supportive measures. Hemodialysis may aid in the removal of cefixime in severe cases.
10. Therapeutic Class
Antibiotics/Antibacterial: Third-generation cephalosporin.
11. Storage Conditions
Store in a cool, dry place away from direct sunlight.
Keep the medication in its original packaging to protect from moisture.
Keep out of reach of children.
12. Chemical Structure
Cefixime Trihydrate has the following chemical formula: C16H15N5O7S2ยท3H2O
The structure consists of a beta-lactam ring, typical of cephalosporins, which is attached to a dihydrothiazine ring. This structure is crucial for its antibacterial activity.