Drugs Used in Acute Pain

Warning

General Notes

Acute pain is often indicative of tissue damage or injury and so can be gauged on a nil > mild > moderate > severe scale and managed according to the WHO 3-Step Ladder.

Pain scoring tools can be useful when considering which step of the WHO Analgesic Ladder a patient should be commenced on.

Choice of drug at each step may vary depending on the cause/type of acute pain and appropriate guidelines for specific pain types should be referred to.

Step 1 Analgesics (Paracetamol +/- NSAID): Pain Score 1–3

Preferred list (P)

PARACETAMOL

  • Consider dose reduction in patients with low body weight (<50kg), renal/hepatic impairment or glutathione deficiency (chronic malnourishment, chronic alcoholism) [NICE CKS].

IBUPROFEN

  • Doses greater than 1.2g daily are associated with increased risk of cardiovascular and gastro-intestinal adverse effects. 

 

Total list (T)

NAPROXEN

Prescribing Notes:

Step 2 Analgesics (Weak Opioid + Paracetamol +/-NSAID): Pain Score 4–6

Preferred list (P)

CO-CODAMOL

Restrictions:

  • Co-codamol 15/500mg strength is non-formulary.

  • Dispersible and effervescent formulations should be restricted to patients with true swallowing difficulties. Their high sodium content (up to 8g daily) exceeds the WHO daily salt intake recommendation of 6g daily and may compromise the treatment of hypertension, heart failure and renal disease.

 

Total list (T)

CODEINE

  • Restriction: For use where flexible dosing is required and providing a combined product would result in administration of potentially unnecessary doses of codeine.

TRAMADOL

  • Restriction: Tramacet® (tramadol 37.5mg/paracetamol 325mg) is non-formulary and is not approved by the SMC for use within NHS Scotland.
  • Capsules are currently the most cost-effective modified release formulation of tramadol.

Tramadol:Morphine Equivalence
(As per BNF online)

 Preparation  Total dose Oral morphine equivalence over 24 hours
Tramadol 50mg Capsules
Two capsules four times a day (400mg)

40mg morphine daily

Tramadol MR Capsules 50mg One capsule twice a day (100mg)

10mg morphine daily

Tramadol MR Capsules 100mg One capsule twice a day (200mg)

20mg morphine daily

Tramadol MR Capsules 150mg One capsule twice a day (300mg)

30mg morphine daily

Tramadol MR Capsules 200mg One capsule twice a day (400mg)

40mg morphine daily

Prescribing Notes:

Only one opioid should be prescribed at a time to optimise beneficial effects and minimise risk of adverse effects.

Codeine

  • At a daily dose of 240mg daily is equivalent to ~ 24mg of oral morphine.
  • Is an inefficient analgesic in approximately 10% of patients who are unable to convert it to morphine [SPC link].

Tramadol

  • Reclassified as a Schedule 3 Controlled Drug in 2014 following a significant increase in the number of deaths associated with its use.
  • Should be avoided in palliative care patients unless specifically requested by a Palliative Medicine Specialist.

Step 3 Analgesics (Strong Opioid + Paracetamol +/-NSAID): Pain Score 7–10

Preferred list (P)

MORPHINE

  • Sustained release preparations of morphine should be prescribed by brand name.

  • Zomorph® is currently the brand of choice within NHS Lanarkshire to ensure continuity between primary and secondary care settings.

    • In patients with true swallowing difficulties Zomorph® capsules can be opened and the contents mixed with semi-solid food (e.g. puree, jam, yoghurt).

    • The contents can also be suspended in water and administered via gastric or gastrostomy tubes of a diameter of more than 16 F.G. with an open distal end or lateral pores [SPC link].

 

Total list (T)

OXYCODONE (immediate-release: Shortec®/modified-release: Oxypro®)

  • Restriction: For management of acute pain only where a patient cannot tolerate oral morphine despite treatment of associated side effects (e.g. constipation, nausea).

Shortec: Morphine Equivalence
(As per BNF online rounded to nearest 5mg)

Preparation Total Dose Oral morphine equivalence over 24 hours
Shortec® 5mg capsules One capsule four times a day (20mg) 30mg morphine daily
Shortec® 10mg capsules One capsule four times a day (40mg) 65mg morphine daily
Shortec® 20mg capsules One capsule four times a day (80mg) 130mg morphine daily

Prescribing Notes:

  • Oxypro® is the preferred brand of modified-release (MR) oxycodone tablets in primary care in NHS Lanarkshire. Immediate-release oxycodone should continue to be prescribed as Shortec®.
  • Only one opioid should be prescribed at a time to optimise beneficial effects and minimise risk of adverse effects.
  • When switching between opioids the dose should be converted and the total daily dose reduced by at least 25%.

NHSL Joint Adult Formulary Key

To indicate the category of a formulary medicine, updated sections adopt the following key:

Preferred list (P): First-line formulary choices.

Total list (T): Alternative choices when preferred list options not effective/not tolerated, or not indicated.

Specialist initiation (S1): Specialist initiation, or on the advice of a Consultant or Specialist Practitioner in this therapeutic area. Continuation in primary care is acceptable.

Specialist use only (S2): Supply via hospital, Homecare Service or a hospital based prescription (HBP) for dispensing by community pharmacy. Not prescribed in primary care setting.

Editorial Information

Last reviewed: 31/01/2022

Next review date: 31/01/2025

Author(s): NHSL.

Version: Please refer to the introduction section for an explanation of the review dates above.

Approved By: ADTC

Reviewer name(s): ADTC.