- Surprising Reasons You're in Pain Slideshow
- Take the Pain Quiz
- Joint-Friendly Exercises to Reduce RA Pain Slideshow
- What is fentanyl-injection, and how does it work (mechanism of action)?
- What brand names are available for fentanyl-injection?
- Is fentanyl-injection available as a generic drug?
- Do I need a prescription for fentanyl-injection?
- What are the side effects of fentanyl-injection?
- What is the dosage for fentanyl-injection?
- Which drugs or supplements interact with fentanyl-injection?
- Is fentanyl-injection safe to take if I'm pregnant or breastfeeding?
- What else should I know about fentanyl-injection?
What is the dosage for fentanyl-injection?
Fentanyl injection can be injected into muscle (intramuscular) or into veins (intravenous). The usual dose for surgical premedication in adults is 0.05 mg to 0.1 mg per dose given by intramuscular injection or by intravenous injection. For anesthesia, the dose is 0.5 to 20 mcg/kg per dose given intravenously. A maintenance intravenous infusion of 1-2 mcg/kg/hour also may be used. There are several recommended regimens for treating pain. Fentanyl also is used for patient-controlled anesthesia (PCA).
Which drugs or supplements interact with fentanyl-injection?
The use of fentanyl with other central nervous system depressants can intensify the depressant effect of fentanyl on breathing, depress the brain, sedate, and lower blood pressure. Other drugs that should be used cautiously with fentanyl include antipsychotics, for example, thorazine, stelazine, and haloperidol (Haldol), anxiolytics, for example, diazepam (Valium), lorazepam (Ativan), and zolpidem (Ambien), certain antihistamines, for example, diphenhydramine (Benadryl) and hydroxyzine (Vistaril), barbiturates, for example, phenobarbital (Donnatal), tricyclic antidepressants, for example, amitriptyline (Elavil, Endep) and doxepin (Sinequan), alcohol, and skeletal muscle relaxants, for example, carisoprodol (Soma), cyclobenzaprine (Flexeril) and baclofen (Lioresal). The use of fentanyl with amiodarone (Cordarone) may result in a slow heart rate. Cimetidine (Tagamet) when used with fentanyl can cause confusion, disorientation, or seizures due to impairment in breathing and brain function.
The monoamine oxidase inhibitor (MAOI) class of antidepressants, for example, isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), selegiline (Eldepryl), and procarbazine (Matulane) significantly increase the action of fentanyl resulting in more side effects. Fentanyl should not be used in patients taking MAOIs or within 14 days of stopping MAOIs.
Combining fentanyl with drugs that reduce activity of liver enzymes that breakdown fentanyl, for example, ritonavir (Norvir), ketoconazole (Nizoral, Extina, Xolegel, Kuric), itraconazole (Sporanox), troleandomycin, clarithromycin (Biaxin, Biaxin XL), nelfinavir (Viracept), nefazadone, amiodarone, amprenavir (Agenerase), aprepitant, diltiazem (Cardizem, Dilacor, Tiazac), erythromycin, fluconazole (Diflucan), fosamprenavir, and verapamil (Calan, Verelan, Verelan PM, Isoptin, Isoptin SR, Covera-HS), may result in an increase in fentanyl blood levels, increasing or prolonging side effects of fentanyl.
Quick GuideChronic Pain: Causes and Solutions
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