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Usual Diluents


Standard Dilutions [Amount of drug] [Infusion volume] [Infusion rate]

[0 - 5000 mcg] [50-250ml] [Titrate]
[1250 mcg] [250 ml] [Titrate]
[2500 mcg] [250 ml] [Titrate]
[5000 mcg] [250 ml] [Titrate]

(May concentrate further)
[2500 mcg] [ 50 ml] (50 mcg/ml)

Stability / Miscellaneous

Stability data:

Drug Stability
Room Temp.
Fentanyl Protect from light. Retain in carton until time of use.
Store at 20 to 25°C (68 to 77°F)
Solution Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit.
Do not administer unless solution is clear and container undamaged. Discard unused portion.

: 2 Days (RT / REF).
Some studies indicate stability up to 30 days.

Minimum dilution: 2500 to 5000 mcg/ 50 ml.

Premedication: I.M., slow I.V.: 50-100 mcg/dose 30-60 minutes prior to surgery

Adjunct to regional anesthesia: I.M., slow I.V.: 50-100 mcg/dose; if I.V. used, give over 1-2 minutes

Severe pain: I.M.: 50-100 mcg/dose every 1-2 hours as needed; patients with prior opiate exposure may tolerate higher initial doses

Adjunct to general anesthesia: Slow I.V.:
Low dose: Initial: 2 mcg/kg/dose; Maintenance: Additional doses infrequently needed
Moderate dose: Initial: 2-20 mcg/kg/dose; Maintenance: 25-100 mcg/dose may be given slow I.V. or I.M. as needed

High dose: Initial: 20-50 mcg/kg/dose; Maintenance: 25 mcg to one-half the initial loading dose may be given as needed

General anesthesia without additional anesthetic agents: Slow I.V.: 50-100 mcg/kg with O2 and skeletal muscle relaxant

Mechanically-ventilated patients (based on 70 kg patient): Slow I.V.: 0.35-1.5 mcg/kg every 30-60 minutes as needed; infusion: 0.7 - 10 mcg/kg/hour

Patient-controlled analgesia (PCA): I.V.: Usual concentration: 50 mcg/mL
Demand dose: Usual: 10 mcg; range: 10-50 mcg
Lockout interval: 5-8 minutes


50 mcg = 0.05 mg = 1 mL

Dosage should be individualized. Some of the factors to be considered in determining the dose are age, body weight, physical status, underlying pathological condition, use of other drugs, type of anesthesia to be used and the surgical procedure involved. Dosage should be reduced in elderly or debilitated patients.

Vital signs should be monitored routinely.

I.Premedication— Premedication (to be appropriately modified in the elderly, debilitated, and those who have received other depressant drugs)—50 mcg to 100 mcg (0.05 mg to 0.1 mg) (1 mL to 2 mL) may be administered intramuscularly 30 to 60 minutes prior to surgery.

II.Adjunct to General Anesthesia— See Dosage Range Chart

III.Adjunct to Regional Anesthesia— 50 mcg to 100 mcg (0.05 mg to 0.1 mg) (1 mL to 2 mL) may be administered intramuscularly or slowly intravenously, over one to two minutes, when additional analgesia is required.

IV.Postoperatively (recovery room)— 50 mcg to 100 mcg (0.05 mg to 0.1 mg) (1 mL to 2 mL) may be administered intramuscularly for the control of pain, tachypnea, and emergence delirium. The dose may be repeated in one to two hours as needed.

Usage in Children: For induction and maintenance in children 2 to 12 years of age, a reduced dose as low as 2 mcg/kg to 3 mcg/kg is recommended.


TOTAL DOSAGE (expressed as fentanyl base)
Low Dose - Moderate Dose - High Dose -
2 mcg/kg (0.002 mg/kg) (0.04 mL/kg) Fentanyl, in small doses is most useful for minor, but painful, surgical procedures. In addition to the analgesia during surgery, Fentanyl may also provide some pain relief in the immediate postoperative period. 2-20 mcg/kg (0.002-0.02 mg/kg) (0.04-0.4 mL/kg) Where surgery becomes more major, a larger dose is required. With this dose, in addition to adequate analgesia, one would expect to see some abolition of the stress response. However, respiratory depression will be such that artificial ventilation during anesthesia is necessary and careful observation of ventilation postoperatively is essential. 20-50 mcg/kg (0.02-0.05 mg/kg) (0.4-1 mL/kg) During open heart surgery and certain more complicated neurosurgical and orthopedic procedures where surgery is more prolonged, and in the opinion of the anesthesiologist, the stress response to surgery would be detrimental to the well being of the patient, dosages of 20-50 mcg/kg (0.02-0.05 mg/kg) (0.4-1 mL/kg) of fentanyl with nitrous oxide/oxygen have been shown to attenuate the stress response as defined by increased levels of circulating growth hormone, catecholamine, ADH, and prolactin. When dosages in this range have been used during surgery, postoperative ventilation and observation are essential due to extended postoperative respiratory depression. The main objective of this technique would be to produce“stress-free” anesthesia.
MAINTENANCE DOSAGE (expressed as fentanyl base)
Low Dose - Moderate Dose - High Dose -
2 mcg/kg (0.002 mg/kg) (0.04 mL/kg) Additional dosages of fentanyl are infrequently needed in these minor procedures. 2-20 mcg/kg (0.002-0.02 mg/kg) (0.04-0.4 mL/kg) 25-100 mcg (0.025 to 0.1 mg) (0.5 to 2 mL) may be administered intravenously or intramuscularly when movement and/or changes in vital signs indicate surgical stress or lightening of analgesia. 20-50 mcg/kg (0.02-0.05 mg/kg) (0.4-1.0 mL/kg) Maintenance dosage (ranging from 25 mcg (0.025 mg) (0.5 mL) to one half the initial loading dose) will be dictated by the changes in vital signs which indicate stress and lightening of analgesia. However, the additional dosage selected must be individualized especially if the anticipated remaining operative time is short.

As a General Anesthetic:
When attenuation of the responses to surgical stress is especially important, doses of 50 mcg/kg to 100 mcg/kg (0.05 mg/kg to 0.1 mg/kg) (1 mL/kg to 2 mL/kg) may be administered with oxygen and a muscle relaxant. This technique has been reported to provide anesthesia without the use of additional anesthetic agents. In certain cases, doses up to 150 mcg/kg (0.15 mg/kg) (3 mL/kg) may be necessary to produce this anesthetic effect. It has been used for open heart surgery and certain other major surgical procedures in patients for whom protection of the myocardium from excess oxygen demand is particularly indicated, and for certain complicated neurological and orthopedic procedures.

As noted above, it is essential that qualified personnel and adequate facilities be available for the management of respiratory depression.

See package insert for WARNINGS and PRECAUTIONS for use of fentanyl with other CNS depressants, and in patients with altered response.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

Fentanyl Citrate Injection, USP equivalent to 50 mcg (0.05 mg) fentanyl/mL, is supplied in single-dose glass containers as follows:

Size Container Package Package Size List No.
2 mL Ampul ten’s 9093
2 mL Fliptop Vial twenty five’s 9094
5 mL Ampul ten’s 9093
5 mL Fliptop Vial twenty five’s 9094
10 mL Ampul five’s 9093
10 mL Fliptop Vial one’s 9094
20 mL Ampul five’s 9093
20 mL Fliptop Vial one’s 9094
50 mL Fliptop Vial one’s 9094

PROTECT FROM LIGHT. Store at 20 to 25°C (68 to 77°F). [See USP Controlled Room Temperature.]

Revised: April, 2007
Printed in USA EN-1504
Hospira, Inc., Lake Forest, IL 60045 USA

Source: [package insert]

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