Doripenem
Doripenem is an injectable carbapenem antibacterial with broad activity against susceptible gram-negative and gram-positive organisms and many anaerobes. Veterinary use is extra-label and uncommon, with much less clinical experience than for some other carbapenems. Its potential role is treatment of selected serious infections caused by organisms resistant to more routinely used agents.
Group
Carbapenem antibacterial
Mechanism of Action
Doripenem binds bacterial penicillin-binding proteins and inhibits the transpeptidation reactions that cross-link peptidoglycan. The resulting disruption of cell-wall assembly leads to bactericidal activity in growing susceptible bacteria. Its structure provides stability against many beta-lactamases and supports activity against selected resistant Enterobacterales and Pseudomonas isolates. Antibacterial effect depends on time above the organism’s minimum inhibitory concentration.
Dose Rates
Dog
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Resistant bacterial infection | 8 mg/kg | IV | Every 8 h | Infuse over 30–60 minutes. |
Cat
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Resistant bacterial infection | 8 mg/kg | IV | Every 8 h | Infuse over 30–60 minutes. |
Indications
- Specialist extra-label treatment of serious infections caused by doripenem-susceptible multidrug-resistant bacteria in companion animals, including selected Pseudomonas aeruginosa, Escherichia coli or Klebsiella infections; veterinary outcome evidence is limited.
Contraindications
- Reserve for culture-supported infections when suitable alternatives are unavailable.
Interactions
- Do not mix with other medicines in the same vial or syringe.
Adverse effects
- Beta-lactam hypersensitivity; possible neurologic reactions
Preparations
| Preparation | Form | Strength | Route |
|---|---|---|---|
| Doripenem 500 mg vial Further dilution required; vial equivalence is not an injection volume. | Injection | 500 mg / vial | IV |
Monitoring and Administration
Infuse over 30–60 minutes. Veterinary regimens are primarily pharmacokinetic rather than clinical efficacy data.
A 500 mg vial is initially suspended with 10 mL diluent, then transferred to 100 mL saline or D5W until clear; approximately 4.5 mg/mL final concentration. Initial suspension is not for direct injection.
Use initial suspension within 1 hour. Final saline infusion: 8 hours at room temperature or 24 hours refrigerated; D5W infusion: 4 hours at room temperature or 24 hours refrigerated, including infusion time. Discard dark amber/brown solution.
Foal use is suggested only by extrapolation; no established large-animal regimen is provided.