| Indication |
For the treatment of the respiratory, skin, soft tissue, and ENT infections caused by H. influenzae (including b-lactamase producing strains), H. parainfluenzae (including b-lactamase producing strains), S. pneumoniae (penicillin-susceptible strains), S. pyogenes, S. aureus (including b-lactamase producing strains), and M. catarrhalis. |
| Pharmacodynamics |
Cefdinir is a third generation cephalosporin with a broad
spectrum of activity against enteric gram-negative rods. Cefdinir is
stable in the presence of some, but not all, b-lactamase enzymes. As a
result, many organisms resistant to penicillins and some cephalosporins
are susceptible to cefdinir. Cephalosporins work the same way as
penicillins: they interfere with the peptidoglycan synthesis of the
bacterial wall by inhibiting the final transpeptidation needed for the
cross-links. This effect is bactericidal. |
| Mechanism of action |
As with other cephalosporins, bactericidal activity of cefdinir
results from inhibition of cell wall synthesis by acting on penicillin
binding proteins (PBPs). |
| Absorption |
Maximal plasma cefdinir concentrations occur 2 to 4 hours postdose
following capsule or suspension administration. Estimated
bioavailability of cefdinir capsules is 21% following administration of a
300 mg capsule dose, and 16% following administration of a 600 mg
capsule dose. Estimated absolute bioavailability of cefdinir suspension
is 25%. Absorption is reduced by approximately 15% when administered
with a high fat meal. |
| Volume of distribution |
- 0.35±0.29 L/kg [adult subjects]
- 0.67±0.38 L/kg [pediatric subjects (age 6 months to 12 years)]
|
| Protein binding |
60%-70%, binding is independent of concentration. |
| Metabolism |
Cefdinir is not appreciably metabolized. Activity is primarily due to parent drug. |
| Route of elimination |
Cefdinir is not appreciably metabolized. Cefdinir is eliminated
principally via renal excretion with a mean plasma elimination half-life
(t½) of 1.7 (±0.6) hours. |
| Half life |
1.7 ± 0.6 hours |
| Clearance |
- renal cl=2 +/- 1 mL/min/kg [healthy]
|
| Toxicity |
Information on cefdinir overdosage in humans is not available. In
acute rodent toxicity studies, a single oral 5600-mg/kg dose produced no
adverse effects. Toxic signs and symptoms following overdosage with
other b-lactam antibiotics have included nausea, vomiting, epigastric
distress, diarrhea, and convulsions. |
