imipenem/cilastatin vs probenecid
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Side-by-side comparison of imipenem/cilastatin and probenecid. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
moderate Known Drug Interaction
Probenecid: Concomitant administration of PRIMAXIN and probenecid results in increases in the plasma level and half-life of imipenem. 7.2 Probenecid Concomitant administration of PRIMAXIN and probenecid results in increases in the plasma level and half-life of imipenem. Therefore, it is not recommended that probenecid be given concomitantly with PRIMAXIN.
Primaxin
Benemid
Primaxin is a strong antibiotic medicine. It fights serious infections in your body caused by certain bacteria.
No summary available.
Primaxin treats serious infections like lung infections and urinary tract infections. It can also treat infections in the belly, female organs, blood, bones, joints, and skin. Primaxin can also treat infections of the heart. However, Primaxin is not for treating meningitis or other central nervous system infections.
Information not available.
Primaxin has two medicines: imipenem and cilastatin. Imipenem kills bacteria by stopping them from building cell walls. Cilastatin helps imipenem work better by preventing its breakdown in your kidneys.
Information not available.
- • Phlebitis (vein irritation)
- • Nausea
- • Diarrhea
- • Vomiting
- • Rash
- • Diarrhea
- • Nausea
- • Yeast infection of the vagina
- • Headache
- • Vomiting
- Pyrexia 87
- Pathogen Resistance 80
- Thrombocytopenia 67
- Electrocardiogram Qt Prolonged 63
- Nausea 62
- Diarrhoea 76
- Dyspnoea 52
- Adenovirus Infection 47
- Asthenia 47
- Fatigue 46
Primaxin can cause serious allergic reactions. Tell your doctor if you are allergic to any beta-lactam antibiotics like penicillins or cephalosporins. Primaxin can also cause seizures, especially if you have a brain problem or kidney problems. It can also cause severe diarrhea from C. difficile. Using Primaxin with valproic acid may cause seizures.
No specific warnings noted.
Not enough studies have been done to know if Primaxin is safe during pregnancy. Tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding.
No pregnancy information available.
How to Read This imipenem/cilastatin vs probenecid Comparison
imipenem/cilastatin is classified in the Carbapenem Antibiotic Combination drug class, while probenecid sits within the Uricosuric Agent class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, imipenem/cilastatin has 359 submissions while probenecid has 268. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known moderate interaction flagged in FDA labeling, attributed to probenecid keeps imipenem in your blood for a longer time and at higher levels than usual.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for imipenem/cilastatin or probenecid.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.