Naltrexone 1 mg/mL (100 mL)

Ingredients

• Naltrexone 100 mg (2 x 50 mg tablets)
• Ascorbic acid 500 mg (powder or crushed tablets)
• Preservative 0.1% (e.g. 1 mL compound hydroxybenzoate solution or 1 mL methyl hydroxybenzoate 10% solution: formula on Pharmac website)
• Glycerol 20 mL
• Water to 100 mL

Method

• Crush naltrexone tablets and triturate with ascorbic acid
• Add glycerol and preservative to make a paste
• Make up to final volume with water

Storage and notes

• Stable for 30 days at room temperature or 60 days in the fridge
• The liquid is very bitter and gritty, if necessary the dose can be mixed with juice or another flavoured drink just prior to administration.

Reproduced with permission from Dave Woods: Fawcett JP, Morgan NC, Woods DJ. Formulation and Stability of Naltrexone Oral Liquid for Rapid Withdrawal from Methadone. Annals of Pharmacotherapy. 1997;31(11):1291-1295.