Pabrinex®/Thiamine in alcohol detoxification (Guidelines)


Parenteral Pabrinex®

Alcohol dependent individuals requiring detoxification should be offered Pabrinex®*.

Patients detoxifying in the community should be given Pabrinex® if they present with features which put them at risk of Wernicke’s encephalopathy (WE) (those with diarrhoea, vomiting, physical illness, weight loss, poor diet). There is a PGD for the administration of intramuscular Pabrinex® in primary care settings on NHS Highland Intranet.

For guidance on use of Pabrinex® see below.

  • Always give Pabrinex® and thiamine BEFORE the administration of carbohydrate or glucose fluids to avoid precipitation of WE.
  • See also ‘The Royal College of Physicians report on alcohol: guidelines for managing Wernicke’s encephalopathy in the Accident and Emergency department’ at:

A presumptive diagnosis of WE should be made with a history of alcohol abuse or current intoxication and one or more of the following unexplained symptoms:

  • acute confusion
  • ophthalmoplegia/nystagmus
  • ataxia
  • memory disturbance
  • comatose/unconscious, hypotension and hypothermia. 

If there is no response to parenteral Pabrinex®, seek specialist advice to rule out alternative diagnoses.

*Parenteral Pabrinex® – two formulations exist, ensure you are using the appropriate formulation for the route prescribed.

Intramuscular Pabrinex®

(store in refrigerator)

Preferred in settings where there are difficulties with intravenous access.


Dose: If symptom(s) present, ONE pair of ampoules twice daily for 3 days then if a response, one pair of ampoules once daily for 5 days, or for as long as improvement continues. If no symptoms present, ONE pair of ampoules once daily for 5 days.                          

Intravenous Pabrinex®

(store at room temperature)

May offer a more rapid response than intra-muscular and is therefore preferred in emergency cases. Prepare by diluting one pair of ampoules in 50 to 100mL sodium chloride 0·9% and administer by intravenous infusion over 30 minutes.

Dose: If symptom(s) present, TWO pairs of ampoules (BNF allows up to 3 pairs) 3 times daily for two days followed by ONE pair of ampoules once daily for up to 5 days, or for as long as improvement continues. If no symptoms present ONE pair of ampoules once daily for 3 to 5 days.

Note: The risk of anaphylaxis is very small with Pabrinex®, however, in accordance with MHRA/CHM guidance, administration of Pabrinex® should only take place when appropriate resuscitation facilities are available. The clinical decision as to when to use intramuscular or intravenous preparation should be based on the local skills, facilities and patient group.

Oral Thiamine

High dose oral thiamine: 200mg to 300mg daily in divided doses.

Two regimes are in use in NHS Highland:

50mg 4 times daily


100mg 3 times daily.

ALL alcohol dependent individuals requiring detoxification should be prescribed high dose oral thiamine along with Pabrinex®.

Consider prescribing high dose oral thiamine for all heavy drinkers.

There is clear consensus that oral thiamine cannot treat WE and may not prevent WE in patients at high risk of WE. In such patients all the guidance is consistent in advising that parenteral thiamine should be employed.

In the longer term, adherence with regimes requiring more than twice daily administration of medication is poor. Some thiamine is probably better than none after the acute phase, if adherence with multiple divided doses is problematic.


Abbreviation Meaning
PGD Patient group direction
MHRA / CHM Medicines and Healthcare products Regulatory Agency / Commission on Human Medicines

Next review date: 01/01/2024

Author(s): Intensive Care .

Reviewer name(s): R Jones, Substance Misuse Pharmacist, Dr B Wallace, Intensive Care Medicine .

Document Id: TAM295