General: Interaction with sodium valproate: CARBAPENEMS may reduce serum valproic acid concentrations to subtherapeutic levels, resulting in loss of seizure control. Serum valproic acid concentrations should be monitored frequently after initiating carbapenem therapy. Alternative antibacterial or anticonvulsant therapy should be considered if serum valproic acid cannot be maintained in the therapeutic range or seizures occur.
Development of drug-resistant bacteria: Prescribing doripenem in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to the patient and increase the risk of the development of drug resistant bacteria.
Pneumonitis with inhalational use: When doripenem has been used investigationally via inhalation, pneumonitis has occurred. Doripenem for Injection should not be administered by this route.
Patients with Renal Impairment: Dosage adjustment is required in patients with moderately or severely impaired renal function in such patients, renal function should be monitored.
Information for Patients: Patients should be counseled that antibacterial drugs including doripenem should only be used to treat bacterial infections. They do not treat viral infections. When doripenem is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by doripenem or other antibacterial drugs in the future.
Use in Children: Safety and effectiveness in pediatric patients have not been established.
Use in Elderly: Of the total number of subjects in clinical studies, 28% were 65 and over, while 12% were 75 and over. Clinical cure rates in complicated intra-abdominal and complicated urinary tract infections where slightly lower in patients ≥65 years of age and also in the subgroup of patients ≥75 years of age versus patients <65. These results were similar between doripenem and Comparator treatment groups.
No overall differences in safety were observed between older and younger subjects, but greater sensitivity of some older individuals cannot be ruled cut.
Elderly subjects had greater doripenem exposure relative to non-elderly subjects; however, this increase in exposure was mainly attributed to age-related changes in renal function.
This drug is known to be excreted substantially by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function or pre-renal azotemia. Because elderly patients are more likely to have decreased renal function or pre-renal azotemia, care should be taken in dose selection, and it may be useful to monitor renal function.