Pristinamycin

Summary

Pristinamycin is a natural mixture of two antibiotics (streptogramin A and B) produced by Streptomyces pristinaespiralis, used orally for susceptible Gram‑positive infections, especially when other agents fail.

Mechanism of Action

Synergistic inhibition of bacterial protein synthesis by binding to distinct sites on the 50S ribosomal subunit; component I blocks the early phase of peptide chain elongation, component II blocks the later phase, together causing a bacteriostatic effect.

Routes of Administration

Goals & Uses

• Treatment of MRSA infectionsAntimicrobialModerate
• Community-acquired pneumonia (mild)Respiratory InfectionLow
• treat bacterial infectionsInfectious DiseaseHigh
• Treatment of streptococcal infectionsAntimicrobial / Infectious DiseaseHigh
• Penicillin-allergic patient infectionsAntimicrobial / Infectious DiseaseModerate
• Treatment of staphylococcal skin and soft tissue infectionsAntimicrobial / Infectious DiseaseHigh

Contraindications

• Severe hepatic impairmentOrganModerateLiver function concerns
• Hypersensitivity to pristinamycin or other streptograminsAllergyHigh
• PregnancyPopulationModeratePotential fetal risk or insufficient safety data
• Pregnancy (especially first trimester)ReproductiveModerate
• Hypersensitivity to streptograminsAllergyHigh

Adverse Effects

• Gastrointestinal upsetGastrointestinalCommon
• AnaphylaxisImmunologicRareSevere life-threatening allergic reaction
• Skin rash / urticariaDermatologicalUncommon
• NauseaGastrointestinalCommonFeeling of sickness or urge to vomit
• VomitingGastrointestinalCommonForceful expulsion of stomach contents
• Rash/pruritusDermatologicUncommon
• Elevated liver enzymesHepaticRareIncrease in AST/ALT or other hepatic markers
• DiarrheaGastrointestinalCommonLoose or frequent stools

Drug Interactions

• CYP3A4 inhibitors (e.g., erythromycin, clarithromycin)Moderate
• WarfarinModerate
• CyclosporineHigh
• Ergot alkaloidsHigh
• Statins (e.g., simvastatin)Moderate

Population Constraints

• PregnancyReproductive SafetyRelative
• Hepatic impairmentOrgan FunctionRelative
• Pediatric patients (< 6 years)PediatricRelative
• BreastfeedingReproductiveRelative
• Children <12 yearsAgeRelative

Regulatory Status

• European UnionApprovedApproved: respiratory tract infections, skin and soft‑tissue infectionsApproved for oral use in adult patients
• United StatesUnapprovedNot FDA‑approved; analogous synthetic product (quinupristin/dalfopristin) is approved
• United KingdomApprovedApproved: respiratory infections, skin infectionsAvailable under prescription

Approved in France (brand name Pyostacine) since the 1960s; not approved by the US FDA or EMA as a standalone product. Quinupristin/dalfopristin, a semi-synthetic IV derivative, is FDA-approved. Pristinamycin is used primarily in France and some European countries.

Evidence & Sources

No sources recorded yet.

Frequently Asked Questions