Piperacillin

Pronunciation: pip-er-a-SIL-in.

Generic name
piperacillin sodium
Drug class
Ureidopenicillin (extended-spectrum, antipseudomonal penicillin antibiotic)
Form
Powder for injection, 2 g/3 g/4 g vials (historical; not currently marketed as a standalone product)
Route
Intravenous or intramuscular injection (historical)
Legal status
Prescription-only, hospital-administered injectable (historical -- monotherapy discontinued)

Availability and supply rules vary by country

Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand

Australia: No current standalone piperacillin brand (4) · Full directory

What piperacillin sodium is and how it works

Piperacillin is an injectable, broad-spectrum antibiotic (a ureidopenicillin) that was historically used alone to treat serious bacterial infections, including infections caused by Pseudomonas aeruginosa. As a standalone (monotherapy) product, it is no longer actively marketed in the United States, United Kingdom, European Union, Canada, Australia, or New Zealand -- it has been fully replaced by the combination product piperacillin/tazobactam, which adds a beta-lactamase inhibitor to overcome bacterial resistance and remains in widespread current use. (1) (2)

This page describes piperacillin as a discontinued standalone antibiotic for historical and reference purposes. If you have been prescribed a piperacillin-containing medicine today, it is almost certainly the combination product piperacillin/tazobactam, which is a separate medicine with its own information page. Like all penicillin-class antibiotics, piperacillin carries a genuine risk of serious, occasionally fatal allergic (hypersensitivity/anaphylactic) reactions, and a risk of Clostridium difficile-associated diarrhea, which can range from mild to life-threatening colitis.

Mechanism of action: how piperacillin sodium works

Piperacillin is a ureidopenicillin that inhibits bacterial cell wall synthesis by binding penicillin-binding proteins, with an extended spectrum of activity including Pseudomonas aeruginosa and many gram-negative organisms; as monotherapy it is susceptible to hydrolysis by many bacterial beta-lactamases, which is why the current combination product adds tazobactam, a beta-lactamase inhibitor. (1)

What piperacillin sodium is used for

Historical use: serious bacterial infections (monotherapy, discontinued)

When it was an actively marketed standalone product, piperacillin was used to treat serious infections including intra-abdominal, urinary tract, gynecologic, and lower respiratory tract infections, septicemia (bloodstream infection), skin and soft tissue infections, bone and joint infections, and uncomplicated gonorrhea, and was used for surgical infection prevention in abdominal, gynecologic, and cesarean-section procedures. It is genuinely discontinued as a standalone product today; these uses are described for historical/reference purposes only. (1)

Before taking piperacillin sodium

Do not take / not appropriate for

  • Piperacillin as a standalone product is not currently marketed in any of the 6 standard markets reviewed for this page -- it cannot be newly prescribed or obtained as a monotherapy product today. (all countries) (2)
  • Historically, piperacillin was contraindicated in anyone with a history of an allergic reaction to any beta-lactam antibiotic, including other penicillins or cephalosporins. (all countries) (1)

Tell your clinician about

  • If you have been told you need 'piperacillin,' confirm with your clinician or pharmacist whether they mean the current combination product piperacillin/tazobactam, since standalone piperacillin is discontinued.
  • Any history of allergic reaction to penicillins, cephalosporins, or other beta-lactam antibiotics.
  • Any history of colitis or antibiotic-associated diarrhea.
(1)

How to take piperacillin sodium

  • Piperacillin as a standalone product is discontinued and not available for new prescriptions in any of the 6 standard markets reviewed for this page.
  • Historically, it was given only by injection (into a vein or muscle) by trained healthcare staff in a hospital or clinical setting -- never self-administered.
(1)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6) (7)

Missed dose

Not applicable -- piperacillin as a standalone product is discontinued and was, when in use, exclusively administered by healthcare staff in a hospital or clinical setting rather than self-scheduled by a patient.

Overdose

Not applicable to current use, since the standalone product is discontinued. Historically, as with other penicillins, excessive doses (especially in people with reduced kidney function) could cause neuromuscular excitability or seizures; any suspected overdose in a clinical setting would require urgent medical assessment. (1)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Injection-site reactions, discomfort, or inflammation.

What to notice: Injection-site reactions, discomfort, or inflammation.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Gastrointestinal upset, including nausea and diarrhea.

What to notice: Gastrointestinal upset, including nausea and diarrhea.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Rash.

What to notice: Rash.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Serious warnings

Signs of a serious allergic (hypersensitivity/anaphylactic) reaction — high caution

Symptoms: Swelling of the face, lips, tongue, or throat; difficulty breathing; widespread rash or hives; sudden drop in blood pressure or collapse.

Action: Seek emergency medical help immediately. The historical FDA label states, verbatim-derived: serious and occasionally fatal hypersensitivity (anaphylactic/anaphylactoid) reactions have been reported in patients on penicillin therapy; a careful history of prior allergic reactions to penicillins, cephalosporins, and other allergens should always be taken before treatment, and a serious reaction requires immediate emergency treatment, including epinephrine. (1)

Signs of Clostridium difficile-associated diarrhea (antibiotic-associated colitis) — high caution

Symptoms: Watery or bloody diarrhea, abdominal pain or cramping, and fever, which can develop during or even after antibiotic treatment ends.

Action: Contact a clinician promptly -- this can range from mild diarrhea to severe, life-threatening colitis and needs medical assessment. (1)

Signs of neuromuscular excitability or seizures (high-dose or reduced kidney function) — high caution

Symptoms: Muscle twitching, confusion, or seizures, historically reported at high doses, particularly in people with reduced kidney function.

Action: Seek urgent medical attention -- this is a recognised risk of high-dose penicillin therapy, especially with impaired kidney clearance. (1)

Interactions

  • As with other penicillins, combining piperacillin with other medicines that affect bleeding, or with other antibiotics, was managed under close clinical supervision in hospital settings historically. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Not applicable to current use since the standalone product is discontinued; historical use required individualised clinician assessment. (1) (2) (3) (4) (5) (6) (7)

Breastfeeding

Not applicable to current use since the standalone product is discontinued; historical use required individualised clinician assessment. (1) (2) (3) (4) (5) (6) (7)

Children

Not specifically quantified for the standalone product in the sources reviewed for this dossier. (1) (2) (3) (4) (5) (6) (7)

Elderly

Not specifically quantified for the standalone product in the sources reviewed for this dossier; historical dosing accounted for kidney function, which commonly declines with age. (1) (2) (3) (4) (5) (6) (7)

Hepatic_impairment

Not specifically quantified in the sources reviewed for this dossier. (1) (2) (3) (4) (5) (6) (7)

Renal_impairment

Historical label notes increased risk of neuromuscular excitability and seizures at high doses in patients with reduced kidney function; dose adjustment was required historically for renal impairment. (1) (2) (3) (4) (5) (6) (7)

Monitoring

Before starting

  • Allergy history to penicillins, cephalosporins, and other beta-lactams
  • Kidney function

During treatment

  • Historically, monitoring for signs of allergic reaction, diarrhea/colitis, and (with prolonged therapy) blood cell counts (leukopenia) and potassium levels (hypokalemia) was recommended.
  • Not applicable to current use, since the standalone product is discontinued.
(1)

Storage

Not applicable -- standalone piperacillin is not currently manufactured or distributed as a marketed product in the 6 markets reviewed for this page.

Study the drug class: Penicillins

Professional information

Clinician-facing context only, sourced from the historical (last revised March 2007) US FDA Pipracil prescribing information; this product is discontinued as a standalone monotherapy and this information is retained for historical/reference purposes only -- verify current prescribing against the piperacillin/tazobactam combination product label for any active treatment decision.

United States (historical)

Indication: Serious systemic infection (monotherapy, discontinued)

Dose summary: 12-18 g/day IV in divided doses every 4-6 hours; usual maximum daily dose 24 g.

Renal context: Dose reduction required in renal impairment; increased risk of neuromuscular excitability/seizures at high doses with reduced clearance. (1)

Mechanism of action

Hepatic guidance

Not specifically quantified in the sources reviewed for this dossier.

Overdose note

Historically, excessive doses (especially with reduced renal clearance) were associated with neuromuscular excitability and seizures; manage with supportive care. (1)

Frequently asked questions

Is piperacillin still available as its own medicine?

No. Research for this page found that standalone piperacillin (piperacillin sodium alone, historically sold as Pipracil) is genuinely discontinued and not currently marketed in the United States, United Kingdom, European Union, Canada, Australia, or New Zealand. A US Federal Register notice confirms it was withdrawn from sale for commercial reasons, not safety or effectiveness. It has been fully replaced by the combination product piperacillin/tazobactam, which remains in wide current use and has its own separate medicine page. (2)

Why does piperacillin carry a penicillin allergy warning?

Because, like all penicillin-class antibiotics, it carries a genuine risk of serious and occasionally fatal allergic (hypersensitivity/anaphylactic) reactions, confirmed in its historical FDA prescribing information. This is why a careful allergy history to penicillins, cephalosporins, and other beta-lactams was always required before treatment. (1)

What should I do if my prescription mentions piperacillin?

Confirm with your clinician or pharmacist -- today, this almost certainly refers to the combination product piperacillin/tazobactam, since standalone piperacillin is no longer marketed anywhere reviewed for this page. (2)

What is the mechanism of action of piperacillin sodium?

Piperacillin is a ureidopenicillin that inhibits bacterial cell wall synthesis by binding penicillin-binding proteins, with an extended spectrum of activity including Pseudomonas aeruginosa and many gram-negative organisms; as monotherapy it is susceptible to hydrolysis by many bacterial beta-lactamases, which is why the current combination product adds tazobactam, a beta-lactamase inhibitor. (1)

What is the generic name of Piperacillin?

The generic name is piperacillin sodium. (1)

What class of drug is piperacillin sodium?

Piperacillin is classed as: Ureidopenicillin (extended-spectrum, antipseudomonal penicillin antibiotic). (1)

References

  1. PIPRACIL (piperacillin sodium) for injection -- full prescribing information (historical label, product discontinued from marketing)U.S. Food and Drug Administration / DailyMed (NIH), historical full prescribing information, Wyeth (last revision 03/2007) · United States · accessed 2026-07-30 · source 1
  2. Determination That PIPRACIL (Piperacillin Sodium) 2-Gram, 3-Gram, and 4-Gram Vials Were Not Withdrawn From Sale for Reasons of Safety or EffectivenessU.S. Federal Register / FDA determination notice · United States · accessed 2026-07-30 · source 2
  3. Medicines containing the active ingredient piperacillin sodium -- emc ingredient listingelectronic medicines compendium (emc), United Kingdom -- ingredient search · United Kingdom · accessed 2026-07-30 · source 3
  4. ARTG search results for piperacillin-containing productsTherapeutic Goods Administration (TGA), Australia -- ARTG search · Australia · accessed 2026-07-30 · source 4
  5. Drug and Health Products Portal search results for piperacillin-containing productsHealth Canada Drug Product Database / Drug and Health Products Portal -- search · Canada · accessed 2026-07-30 · source 5
  6. Medsafe data sheet search results for piperacillin-containing productsMedsafe (New Zealand Medicines and Medical Devices Safety Authority) -- data sheet search · New Zealand · accessed 2026-07-30 · source 6
  7. EMA search results for piperacillin-containing productsEuropean Medicines Agency (EMA) -- search · European Union · accessed 2026-07-30 · source 7

Brand names by country

Single-ingredient piperacillin sodium names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • Pipracil (discontinued) (1) (2)FDA orange book discontinued drug product list confirmed · 2 g, 3 g, 4 g vials (historical) · Wyeth (historical)

United Kingdom

  • No current standalone piperacillin brand (3)emc ingredient search only combination products confirmed · not applicable · not applicable

Canada

  • No current standalone piperacillin brand (5)Health Canada portal search only combination products confirmed · not applicable · not applicable

Australia

  • No current standalone piperacillin brand (4)TGA ARTG search only combination products confirmed · not applicable · not applicable

New Zealand

  • No current standalone piperacillin brand (6)Medsafe datasheet search only combination products confirmed · not applicable · not applicable
View brands in additional countries.

European Union

No current standalone piperacillin brand (7)

This page describes piperacillin as a discontinued standalone antibiotic for historical and reference purposes; it is not a substitute for advice from a clinician about any current treatment. If you have been prescribed a piperacillin-containing medicine today, discuss it with your clinician or pharmacist, since it is almost certainly the combination product piperacillin/tazobactam.

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