Syringe drivers (unsuitable drugs)

• Chlorpromazine: Highly irritant; causes severe injection-site reactions and tissue damage.
• Prochlorperazine: Unsuitable for subcutaneous infusion due to high local irritation risk.
• Diazepam: Insoluble in standard aqueous diluents and causes severe pain or inflammation at the site.
• Dexamethasone: Prone to unpredictable precipitation in mixtures and it also inactivates glycopyrronium bromide. This problem may be solved by using hyoscine hydrobromide instead of glycopyrronium bromide. Alternatively, dexamethasone could be given as a separate once-daily injection.
• Diclofenac: Highly incompatible with most palliative drug combinations and requires a dedicated, separate device if used

To a lesser degree, local irritation may be caused by cyclizine. Levomepromazine can be given as a single daily injection in place of cyclizine

Water for injection is most commonly used to dilute the drugs. However, saline is recommended for some drugs and may be used if there are problems with site irritation. Saline should not be used with cyclizine, as it can cause precipitation.

Reference:

1. Scottish Palliative Care Guidelines: Syringe Pumps; Scottish Partnership for Palliative Care. NHS Scotland, 2018.