Zanamavir Intravenous Infusion for Adults

Who can administer

May be administered by registered competent doctor or nurse/midwife

Important information

• Zanamivir  is indicated for the treatment of complicated and potentially life-threatening influenza A or B virus infection  when:
  • The patient's influenza virus is known or suspected to be resistant to anti-influenza medicinal products other than zanamivir ^{(ref 1)} OR
  • Other anti-viral medicinal products for treatment of influenza, are not suitable for the individual patient.  ^{(ref 1,3)} AND the patient has multi-organ involvement, or requires intensive care ^{(ref 2)}
  • Use should be supervised by a consultant clinical microbiologist/virologist or infectious diseases consultant and a consultant in intensive care medicine ^{(ref 3)} 
• Treatment should commence as soon as possible and usually within 6 days of the onset of symptoms ^{(ref 2)}
• See under 'Dose' for adjustments required in renal impairment

Available preparations

Dectova 200mg per 20ml (10mg/mL) vial

Reconstitution

Already in solution

Infusion fluids

Sodium Chloride 0.9% ONLY

Methods of intravenous administration

Intermittent intravenous infusion (using an electronically controlled infusion device)

• Add the required dose to infusion fluid to make a final volume of 100ml or 250ml
  • Withdraw and discard a volume (equal to the volume of drug solution) from the infusion bag
• The infusion bag should be gently manipulated by hand to ensure it is mixed thoroughly
• Administer over 30 minutes ^{(ref 1,3)}
• See also under Further information- re administration undiluted

Dose in adults

Usual dose

• Give 600mg every 12 hours for 5 to 10 days ^{(ref 2)}

Renal impairment

• See Table 1 below

Table 1: Doses in renal impairment
CrCl (mL/min)	Initial dose	Maintenance dose	Maintenance dose schedule
50 to < 80	600mg	400mg every 12 hours	Begin Maintenance dose 12 hours AFTER initial dose
30 to < 50	600mg	250mg every 12 hours
15 to < 30	600mg	150mg every 12 hours	Begin Maintenance dose 24 hours AFTER initial dose
< 15	600mg	60mg (SIXTY) every 12 hours	Begin Maintenance dose 48 hours AFTER initial dose

Hepatic impairment

• No dose modification is required

Elderly

• No dose modification is required

Monitoring

• Monitor temperature, blood pressure, heart rate, respiratory rate, O² saturation, behavioural changes, and injection site reaction ^{(ref 3)}
• Can increase ALT and AST and cause hepatocellular injury (1%)
• Common side effects are rash, ALT/AST increase and diarrhoea ^{(ref 1,3)}

Further information

• Can give undiluted over 30 minutes via electronically controlled device
• No dose adjustment is required for elderly patients

Storage

Store below 25⁰C

References

SPC - Dectova  01/10/2019
1. Zanamivir - BNF, accessed online via medicines complete  17/01/2024
2. Guidance on the use of antiviral agents for the treatment and prophylaxis of Influenza, HSE, December 2023
3. Injectable medicines guide NHS Medusa Injectable Medicines Guide, downloaded 17/01/2024

Therapeutic classification

Direct Acting Antivirals - Neuraminidase inhibitors - J05AH