Prescribing for the syringe driver
Which medications should I prescribe?
Four groups of drugs are commonly prescribed:
- Analgesics (usually morphine or diamorphine)
- Anti-emetics (haloperidol, cyclizine, metoclopramide, levomepromazine)
- Sedatives (midazolam)
- Anti-secretory drugs (hyoscine hydrobromide, glycopyrrollate)
Typical doses and indications are listed in the Brief guide to drugs for the syringe driver.
Prescriptions are generally written as dose/24 hours. Unless you are prescribing the maximum 24 hour dose in the syringe driver, an additional prescription for prn bolus doses through a separate butterfly (with frequency and maximum 24 hour dose) is helpful.
Additional prn bolus doses of analgesia should always be prescribed and available for administration by nursing staff as required.
What diluent is best to use?
Water is generally recommended unless there are problems with site irritation.
- Saline should not be used with cyclizine as it can cause precipitation.
- Saline may improve site irritability problems with levomepromazine.
Can I mix medications in the same syringe?
Generally there are few compatibility problems with common two and three drug combinations containing:
- Hyoscine Hydrobromide
Watch out for problems with:
- Cyclizine with diamorphine once diamorphine exceeds 200mg/24 hours.
- Ketorolac (many incompatibilities)
- Dexamethasone (common/unpredictable precipitation)
Incompatibility problems can usually be resolved by changing the drugs, giving a drug as a single daily injections, or as a last resort, setting up two syringe drivers.
|Cyclizine||Precipitates with saline and with diamorphine doses exceeding 200mg/24 hours.||Use water as diluent. At higher diamorphine doses, either put cyclizine in a second syringe driver or use levomepromazine as a single daily SC injection instead.|
|Ketorolac||Incompatible with many drugs||Use a separate syringe driver|
|Dexamethasone||Inactivates glycopyrrollate. Common and unpredictable precipitation with other drugs.||Use hyoscine hydrobromide instead of glycopyrrollate Give dexamethasone as separate once daily injection.|
|Hyoscine butyl bromide (Buscopan)||Occasional incompatibility with cyclizine.||Give levomepromazine as a single daily injection in place of cyclizine.|
Table: Solutions to drug incompatibility problems
More detailed information is available from:
- Your local palliative care team
- Drug information services
- Pharmacists serving specialist inpatient units
- Syringe drivers have helped transform delivery of palliative care in the home setting and skill in their use is vital.
- The syringe driver may be used in any situation when the patient is unable to take oral medication.
- A syringe driver is only an alternative method of administering medication. It does not produce more effective analgesia than the oral route unless the patient cannot use oral medication or has serious compliance problems, nor should it be routinely used as a 'medical last rite' if there is no specific indication for medication.
- Where local guidelines or protocols are available, the primary care team should access and follow them.
- Syringe drivers should only be set up by staff trained and competent in their use.
- Different types of syringe driver are used in different areas. This often causes confusion and sometimes causes serious hazard when staff move from one area to another.
- It is vitally important to check the model of syringe driver you are using, to ensure you are familiar with it and to follow the manufacturers guidelines for that model carefully.
- Syringe driver prescriptions are written as the total dose/24 hours. As necessary bolus doses may still be required, especially for painkillers.
- The prescriber should be aware of potential drug incompatibilities, and know where to access detailed information.
The syringe driver: Continuous subcutaneous infusions in palliative care Andrew Dickman, Jennifer Schneider, James Varga (2nd edition) 2005 Oxford University Press
Department of Health, London Doing no harm The medical devices directorate 1994
Department of Health, London The report of the expert working group on alarms and clinical monitors The medical devices directorate 1995
MS16A and MS26 Instruction manual. SIMS Graseby 1998
Oliver DJ Syringe drivers in palliative care: a review Palliative Medicine 1988 2 21-26
Symptom management in advanced cancer Robert Twycross, Andrew Wilcock (3rd edition) Radcliffe Medical Press
A Guide to symptom relief in advanced cancer Claud Regnard, Sue Tempest (5th edition,) 2004 Radcliffe Medical Press
ABC of Palliative care Marie Fallon, Geoff Hanks (Eds) 2006 Blackwell
Palliative Care Formulary Robert Twycross, Andrew Wilcock (3rd edition) 2007 Palliativedrugs.com Ltd.
© Dr. Eileen Palmer, Dr John Howarth Palliative Care for the
Primary Health Care Team (2009) Quay Books ISBN 1856422291
© Palliative care syringe driver pack 2 Dr Eileen Palmer 2009