Fentanyl Patch Application Site
Yes, a fentanyl transdermal patch can be applied to multiple locations on the body, but specific anatomical sites are recommended and certain areas must be avoided to ensure safe and effective drug delivery.
Approved Application Sites
The FDA-approved application sites vary by patient population 1:
For Adults:
- Chest
- Back
- Flank (sides of the waist)
- Upper arm
These sites should be hairless or have minimal hair 1.
For Children and Adults with Mental Impairment:
- Upper back only - This specific placement reduces the risk that the patient will remove the patch and place it in their mouth, which could be fatal 1.
Critical Site Selection Criteria
The skin must meet specific requirements regardless of location 1:
- Must NOT be oily, burned, broken out, cut, irritated, or damaged in any way
- Avoid areas that are highly sensitive or move excessively during normal activity
- If hair is present, clip it close to the skin rather than shaving (shaving causes irritation that impairs absorption) 1
Pharmacokinetic Rationale
The fentanyl molecule's high lipid solubility and low molecular weight facilitate absorption through intact skin, creating an intradermal depot that releases drug systemically over 72 hours 2. This property allows flexibility in site selection as long as the skin integrity requirements are met 3, 4.
Critical Safety Consideration
Never place the patch in locations that may be exposed to external heat sources 2, 5. If a patch location will be under a forced hot-air warmer (such as during surgery), it must be removed and replaced at a different site, as heat exposure significantly accelerates fentanyl release and can cause fatal overdose 2, 5.
Site Rotation
When changing patches every 72 hours, apply the new patch to a different skin site to prevent local skin irritation 1. Only 3% of patients experience transient skin irritation, typically related to the adhesive rather than the drug itself 3.