Prescribing calls
Podcast: Play in new window | Download
Sam and Vani explore the most common requests for after hours prescribing and how to safely and quickly approach prescribing of insulin, warfarin, analgesia, antiemetics, and sleeping tablets.
Insulin
- Generally treat any blood glucose of 20 or above.
- Target range:
- Inpatient: 7 – 14 mmol/L
- Outpatient: 4 – 10 mmol/L
- Achieving target 60% of the time is quite good!
- Neglecting high BSLs leads to irritating symptoms, opportunistic infections and delayed recovery.
- Correct BSLs with a rapid acting insulin (Novorapid)
- Correction doses should be given at meals and no more frequently than 4 hourly.
- If correction doses of insulin are required, consider increasing the person’s usual insulin / treatment.
- Don’t recheck BSLs too early. Wait until the next scheduled check, unless there is concern of hypoglycaemia.
- Don’t use ActRapid – it works slowly subcut so should only be used IV.

- Diabetes in pregnancy requires frequent adjustment and tighter control – consult a senior.
- Don’t withhold long acting insulin (Lantus and insulin degludec) if NBM, even if on a GIK.
Antiemetics
- Cyclizine (NZF)
- Antihistimine
- Classic, old-school, and effective
- Great for non-iatrogenic nausea and vomiting
- Can give euphoria IV, so avoid in young patients specifically requesting it and in the elderly
- 25 – 50 mg PO/IV TDS PRN
- Ondansetron (NZF)
- Serotonin antagonist
- Newer, but not necessarily better antiemetic
- Primarily indicated for PONV and chemotherapy-induced nausea
- Can be constipating
- Can reduce the effectiveness of tramadol, so avoid co-prescription
- 10 mg PO/IV TDS PRN
- Metoclopramide (NZF)
- Dopamine antagonist
- Gastric stimulant, avoid in suspected small bowl obstruction
- Avoid co-prescribing with droperidol and prochlorperizine
- Avoid in Parkinson’s disease
- Avoid in under 20 year olds due to risk of oculogyric crisis
- 10 mg PO/IV TDS PRN
- Domperidone (NZF)
- Somewhat interchangeable with metoclopramide, but no IV formulation
- Does not cross BBB, so preferred in Parkinson’s disease
- 10 mg PO TDS PRN
- Droperidol (NZF)
- Dopamine antagonist
- Usually prescribed by anaesthetics for PONV
- 0.625–1.25 mg IV Q6H PRN
- Scopoderm patch (NZF)
- Nonspecific antimuscarinic
- Usually prescribed by anaesthetics for PONV
- 1 patch Q72H
- Prochlorperazine (NZF)
- Oral: 20 mg initially then 10 mg after 2 hours; prevention 5–10 mg 2–3 times daily
- Rectal: 25 mg when required followed if necessary after 6 hours by an oral dose, as above
- Don’t confuse with chlorpromazine!
Analgesia
- Pain assessment
- Try to get some kind of assessment documented e.g. verbal pain score
- Pain ladder
- Simple analgesia e.g. paracetamol +/- NSAID
- “Weak” opioides e.g. tramadol or codeine
- Titrate up opiates e.g. morphine or oxycodone
- It may be necessary to “get on top” of the pain first with some IV boluses, then once the patient is comfortable, some low-dose long acting analgesia may be all that is required.
- If possible, please avoid opiates in young patients (e.g. <25 years) as there is a strong link between opiate exposure in the young and subsequent drug and alcohol dependance and abuse. First do no harm!
Sleeping tablets
- Very common request on evening and ward calls
- Balance benefit with risk
- Patients need sleep to recover from the illness, so don’t withhold unnecessarily
- However don’t contribute to an avoidable fall
- Zopiclone (NZF)
- 7.5 – 15 mg PO nocte
- Generally first line unless the patient already uses an alternative
- Quetiapine (NZF)
- Antipsychotic, not indicated for insomnia
- However patient who have tried it tend to swear by it
- Use as a sleeping tablet in low dose (e.g. 25 mg) is off-label, so generally avoid unless the patient already uses it.
- Benzodiazepines
- Temazepam (NZF) 10 – 20 mg PO nocte
- Generally avoid benzos unless you are experienced with their use, as they have many interactions and dependance is rapid.