TIGGY

Indications

• Complicated skin and skin structure infections
• Complicated intra-abdominal infections
• Community-acquired pneumonia
• Non-gonococcal urethritis

Dosage

Children: Child 12–17 years: 500 mg IV every 12 hours for 7–14 days. Refer to the BNF for Children for specific dosing guidance.

Adults: Initial dose of 200 mg IV followed by 100 mg IV every 12 hours. Duration of treatment varies based on the infection but typically lasts 5 to 14 days.

Mechanism of action

Tigecycline exerts its antimicrobial effect by inhibiting protein synthesis in bacteria. It binds to the 30S ribosomal subunit, blocking the attachment of aminoacyl-tRNA to the ribosomal acceptor site, thereby preventing the incorporation of amino acids into peptide chains. This action ultimately disrupts bacterial growth and reproduction.

Pharmacodynamics

Tigecycline demonstrates time-dependent bacteriostatic activity. Its effectiveness is influenced by the duration of exposure rather than peak concentration. The drug has a broad spectrum of activity against both aerobic and anaerobic bacteria, including resistant strains of Staphylococcus aureus and Enterococcus faecalis. It is important to note that tigecycline has no activity against Pseudomonas aeruginosa.

Pharmacokinetics

Tigecycline is administered intravenously and has a volume of distribution of approximately 7-10 L/kg, indicating extensive tissue distribution. It is partially metabolized in the liver and primarily excreted in feces, with a half-life of about 27 hours. Renal impairment does not significantly affect tigecycline clearance, but caution is advised in severe cases. The drug is not removed by dialysis.

Contra-indications

• Children under 12 years
• Diabetic foot infections

Adverse effects

• Decreased appetite
• Diarrhoea
• Dizziness
• Gastrointestinal discomfort
• Agranulocytosis
• Aplastic anaemia
• Nephritis
• Renal impairment
• Toxic epidermal necrolysis
• Hepatotoxicity

Interactions

• Carbamazepine (decreases exposure)
• Antifungals, azoles (increases exposure)
• Verapamil (increases exposure)
• Coumarins (affects anticoagulant effect)
• Ivacaftor (increases exposure)
• Lapatinib (increases exposure)
• Macrolides (increases exposure)
• Neratinib (increases exposure)
• Phenindione (increases anticoagulant effect)
• Ranolazine (increases exposure)

Precautions

• Caution in cholestasis
• Caution in hepatic impairment
• Caution in renal impairment

Pregnancy

Tetracyclines should not be given to pregnant women as they can affect skeletal development and may cause discoloration of the child's teeth.

Breast-feeding

Manufacturer advises avoiding use as tigecycline is present in milk in animal studies.

Storage

Store at room temperature, protect from light, and keep out of reach of children.

Formulations

• Tigecycline 50 mg powder for solution for infusion
• Tigecycline 50 mg tablet