Imipenem Cilastatin (Primaxin Iv) — Compare Prices at US & Canada Pharmacies

Imipenem-cilastatin (brand Primaxin IV) is a carbapenem — the broadest-spectrum class of beta-lactam antibiotics — combined with cilastatin, a compound that has no antibacterial activity of its own but blocks a kidney enzyme that would otherwise break imipenem down before it can work. That pairing is what makes the drug effective; imipenem alone is destroyed too quickly by the kidneys to reach therapeutic levels. The combination covers an unusually wide range of Gram-positive, Gram-negative, and anaerobic bacteria, which is why it's reserved for severe, mixed, or hospital-acquired infections — intra-abdominal infections, complicated skin and soft-tissue infections, and infections in critically ill patients where the causative organism isn't yet known and broad coverage is needed while cultures are pending.

The main safety issue specific to this carbapenem is seizure risk, which is higher with imipenem-cilastatin than with other carbapenems such as meropenem or ertapenem. Risk rises with high doses, impaired kidney function (since the drug and metabolites accumulate), pre-existing CNS disorders, and advanced age — clinicians dose-adjust for renal function and use caution or choose an alternative carbapenem in patients with a seizure history. As with other beta-lactams, cross-reactivity in patients with severe penicillin allergy is possible, and it's generally avoided in that setting.

Carbapenems like imipenem-cilastatin are also a focal point of antibiotic stewardship: because they're often a last broad-spectrum option before truly resistant infections require even more specialized drugs, hospitals track and limit carbapenem use to slow the spread of carbapenem-resistant organisms — one reason WHO's AWaRe framework places this drug class in the Watch category rather than Access.

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Contraindications

4 CONTRAINDICATIONS Piperacillin and tazobactam for injection is contraindicated in patients with a history of allergic reactions to any of the penicillins, cephalosporins, or beta-lactamase inhibitors. Patients with a history of allergic reactions to any of the penicillins, cephalosporins, or beta-lactamase inhibitors. ( 4 )

Known drug interactions

7 DRUG INTERACTIONS Piperacillin and Tazobactam for Injection administration can significantly reduce tobramycin concentrations in hemodialysis patients. Monitor tobramycin concentrations in these patients. ( 7.1 ) Probenecid prolongs the half-lives of piperacillin and tazobactam and should not be co-administered with Piperacillin and Tazobactam for Injection unless the benefit outweighs the risk. ( 7.2 ) Co-administration of Piperacillin and Tazobactam for Injection with vancomycin may increase the incidence of acute kidney injury. Monitor kidney function in patients receiving Piperacillin and Tazobactam for Injection and vancomycin.

Pregnancy & breastfeeding

8.1 Pregnancy Risk Summary Piperacillin and tazobactam cross the placenta in humans. However, there are insufficient data with piperacillin and/or tazobactam in pregnant women to inform a drug-associated risk for major birth defects and miscarriage. No fetal structural abnormalities were observed in rats or mice when piperacillin/tazobactam was administered intravenously during organogenesis at doses 1 to 2 times and 2 to 3 times the human dose of piperacillin and tazobactam, respectively,…