ampicillin/sulbactam vs probenecid

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Side-by-side comparison of ampicillin/sulbactam and probenecid. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

minor Known Drug Interaction

Drug Interactions Probenecid decreases the renal tubular secretion of ampicillin and sulbactam. Concurrent use of probenecid with UNASYN may result in increased and prolonged blood levels of ampicillin and sulbactam.

Drug Class
ampicillin/sulbactam Penicillin / Beta-Lactamase Inhibitor
probenecid Uricosuric Agent
Type
ampicillin/sulbactam Prescription
probenecid Prescription
Summary
ampicillin/sulbactam

Unasyn is a combination of two antibiotics that fights bacteria in your body. It contains ampicillin and sulbactam.

probenecid

No summary available.

What It Treats
ampicillin/sulbactam

Unasyn treats skin infections, infections in the stomach area, and infections in women's reproductive organs. It is used when these infections are caused by certain types of bacteria. Your doctor will test to make sure Unasyn is the right medicine for your infection.

probenecid

Information not available.

How It Works
ampicillin/sulbactam

Ampicillin kills bacteria. Sulbactam helps ampicillin work better by preventing bacteria from breaking down ampicillin. Together, they stop the growth of bacteria.

probenecid

Information not available.

Common Side Effects
ampicillin/sulbactam
  • Pain at the injection site
  • Diarrhea
  • Rash
probenecid
  • Diarrhea
  • Nausea
  • Yeast infection of the vagina
  • Headache
  • Vomiting
FAERS Reports
ampicillin/sulbactam
  • Pyrexia 71
  • Pneumonia 44
  • Condition Aggravated 37
  • Acute Kidney Injury 29
  • Rash 29
probenecid
  • Diarrhoea 76
  • Dyspnoea 52
  • Adenovirus Infection 47
  • Asthenia 47
  • Fatigue 46
Serious Warnings
ampicillin/sulbactam

You should not take Unasyn if you have had a severe allergic reaction to penicillins or cephalosporins. You should also not take it if you have had liver problems caused by Unasyn in the past.

probenecid

No specific warnings noted.

Pregnancy
ampicillin/sulbactam

Tell your doctor if you are pregnant or plan to become pregnant. It is not known if Unasyn will harm your unborn baby. Talk to your doctor about the risks and benefits of taking Unasyn while breastfeeding.

probenecid

No pregnancy information available.

Also Compare, Nearby Drugs

Compare ampicillin/sulbactam with

How to Read This ampicillin/sulbactam vs probenecid Comparison

ampicillin/sulbactam is classified in the Penicillin / Beta-Lactamase Inhibitor 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, ampicillin/sulbactam has 210 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 minor interaction flagged in FDA labeling, attributed to one medicine slows down how fast your kidneys remove the antibiotic, which causes the antibiotic to stay in your blood longer.. 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 ampicillin/sulbactam or probenecid.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.