Makindo Medical Notes

⚠️ Always check for penicillin allergy before prescribing.

📖 About

Always check the BNF link here.

• 💊 Piperacillin–Tazobactam (Tazocin, US: Zosyn) – combination of piperacillin 4 g and tazobactam 0.5 g per vial.
• 👩‍⚕️ Broad-spectrum coverage – particularly useful in Pseudomonas and severe hospital-acquired infections.
• Often used in neutropenic sepsis and ICU patients with severe sepsis.
• May be combined with gentamicin for synergy in critically ill patients.

⚡ Mechanism of Action

• 🔪 Piperacillin: bactericidal, inhibits bacterial cell wall synthesis.
• 🛡️ Tazobactam: beta-lactamase inhibitor, protecting piperacillin from enzymatic destruction.
• 🤝 Synergistic when combined with aminoglycosides (e.g. gentamicin).

🧬 Antimicrobial Spectrum

• ✅ Gram-positive aerobes: Streptococci, Staphylococcus aureus (not MRSA).
• ✅ Gram-negative aerobes: E. coli, Klebsiella, Haemophilus influenzae, Acinetobacter, Pseudomonas aeruginosa.
• ✅ Anaerobes: including Bacteroides fragilis group.
• ❌ Not effective against MRSA, VRE, or atypical organisms (e.g. Mycoplasma, Chlamydia).

🩺 Indications

• Severe pneumonia (including hospital- and ventilator-associated).
• Complicated intra-abdominal infections.
• Complicated UTIs and pyelonephritis.
• Skin and soft tissue infections (e.g. diabetic foot, necrotising fasciitis as part of combination therapy).
• Neutropenic sepsis (often with gentamicin).
• Bone marrow transplant or immunocompromised patients with resistant coliform infections.

💊 Dosing – Piperacillin–Tazobactam (verify with BNF/datasheet)

• 📉 Dose reduction required in renal impairment (see BNF/local policy).

🔄 Interactions

• ⬆️ Nephrotoxicity risk when combined with aminoglycosides – monitor renal function closely.
• ⬆️ Increased risk of bleeding with anticoagulants (affects platelet aggregation).
• ⬆️ May raise methotrexate levels (reduced clearance).
• Possible reduced efficacy of oral contraceptives (advise precautions).

⚠️ Cautions

• Renal impairment → adjust dosing to avoid accumulation.
• Liver impairment → monitor LFTs if prolonged therapy.
• Prolonged use can predispose to C. difficile colitis and resistant organisms.

🚫 Contraindications

• Known penicillin allergy (consider alternatives e.g. meropenem if safe).

💥 Side Effects

• 🤢 GI: nausea, vomiting, diarrhoea, antibiotic-associated colitis.
• 🫁 Allergy: rash, urticaria, angioedema, anaphylaxis.
• 🩸 Haematological: haemolytic anaemia, leucopenia, thrombocytopenia.
• 🩺 Renal: interstitial nephritis.
• 🧪 Hepatic: jaundice, hepatitis, abnormal LFTs.
• ⚠️ Severe skin reactions: Stevens–Johnson syndrome, TEN (rare).
• 💉 Hypoglycaemia reported with high-dose/prolonged use.

📑 References

• BNF: Piperacillin–Tazobactam
• NICE Antimicrobial Guidance