Introduction

Name

• Fentanyl.

Class of drug

• Analgesic.
• Opioid analgesic (narcotic).
• Phenylpiperidene derivative.

Description

Chemical name

• N-phenyl-N-[1-(2-phenylethyl)piperidin-4-yl]propanamide

Molecular formula

• C22H28N2O

Molecular weight

• 336.47

Physical properties

• Clear, colorless solution for injection.
• 1 ml solution contains 0.05 mg (50 micrograms) fentanyl (equivalent to 0.0785 mg fentanyl citrate).

Storage requirements

• Shelf-life after opening 28 days.
• Do not freeze.
• Store together with product information.
• If diluted (see Interactions) use immediately to ensure sterility. Dilutions may be stable chemically and physically for 4 hours at 25°C.
• Must meet the storage requirements for a Schedule II controlled drug Controlled drugs: legal requirements for storage, prescription and supply.

Uses

Indications

• Analgesia:
  • For intra-operative analgesia during surgical procedures such as soft tissue and orthopedic surgery.
  • For the control of post-operative pain associated with major orthopedic and soft tissue surgery.
  • For premedication in cardiovascular unstable patients.
• Given:
  Either Alone.
  Or In combination with other anaesthetic agents, eg diazepam Diazepam or midazolam Midazolam. Often used as a balanced anesthetic maintenance protocol.

Administration

Precautions

Interactions

with other drugs

• Potent anesthetic sparing substance:
  • To avoid anesthetic overdose, administer anesthetic agents until the desired effect is produced in dogs administered fentanyl.
• Potential for additive or synergistic effects:
  • Caution in conjunction with morphine or other opioid type analgesics including codein-based antitussives.
  • Caution in conjunction with alpha-2 adrenergic agonists.
• Plasma concentrations may be increased by agents that reduce hepatic metabolism, eg Cimetidine Cimetidine :
  • Do not mix with injection fluids containing:
    • Meloxicam Meloxicam.
    • Other non-aqueous solutions.

Adverse Reactions

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Kukanich B, Clark T P (2012) The history and pharmacology of fentanyl: relevance to a novel, long-acting transdermal fentanyl solution newly approved for use in dogs. J Vet Pharmacol Ther 35 (Suppl 2), 3-19 PubMed.
• Biricik H S, Ceylan C & Sakar M (2004) Effects of pethidine and fentanyl on tear production in dogs. Vet Rec 155 (18), 564-565 PubMed.

Other sources of information

• National Office for Animal Health. Product datasheet Fentadon 50 microgram/mL solution for injection for dogs. Datasheet.
• Based on Small Animal Formulary. Ramsey I (2011) 7th edn. Cheltenham: BSAVA.