Transdermal: Difference between revisions

Revision as of 15:43, 9 February 2025

A method of delivering medication through the skin

Transdermal refers to the method of delivering medication through the skin. This method is used to provide a controlled release of medication into the bloodstream over a period of time. Transdermal delivery systems are often used for medications that require steady blood levels and are an alternative to oral or injectable routes.

Mechanism

Transdermal drug delivery involves the application of a drug formulation onto the skin, where it is absorbed into the bloodstream. The skin acts as a barrier, and the drug must penetrate the outer layer, the stratum corneum, to reach the systemic circulation. This is achieved through the use of transdermal patches, which are designed to adhere to the skin and release the drug at a controlled rate.

Advantages

Transdermal delivery offers several advantages over other routes of administration:

**Avoidance of the gastrointestinal tract**: This method bypasses the digestive system, reducing the risk of gastrointestinal side effects and drug degradation by stomach acids.
**Improved patient compliance**: Transdermal patches are easy to apply and can be worn for extended periods, reducing the frequency of dosing.
**Controlled release**: The delivery system can be designed to release the drug at a constant rate, maintaining steady blood levels.

Disadvantages

Despite its benefits, transdermal delivery also has limitations:

**Skin irritation**: Some patients may experience irritation or allergic reactions at the site of application.
**Limited drug types**: Only drugs that are potent and have suitable molecular properties can be effectively delivered transdermally.
**Variable absorption**: Factors such as skin condition, age, and site of application can affect drug absorption.

Applications

Transdermal patches are used for a variety of medications, including:

Nicotine replacement therapy for smoking cessation.
Hormone replacement therapy, such as estrogen patches.
Pain management with opioid patches like fentanyl.
Cardiovascular disease treatment with nitroglycerin patches.

History

The concept of transdermal drug delivery has been around for centuries, with early examples including the use of herbal poultices. Modern transdermal patches were developed in the 1970s, with the first FDA-approved patch being a scopolamine patch for motion sickness in 1979.

Research and development

Ongoing research in transdermal delivery focuses on improving patch technology, enhancing drug penetration, and expanding the range of drugs that can be delivered transdermally. Innovations include microneedle patches and iontophoresis, which use electrical currents to enhance drug delivery.

Related pages

References

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-'''Transdermal''' is a route of administration wherein active ingredients are delivered across the skin for systemic distribution. Examples include transdermal patches used for medicine delivery, and transdermal implants used for medical or aesthetic purposes.
+{{Short description|A method of delivering medication through the skin}}
+{{Use dmy dates|date=October 2023}}
-== Overview ==
+'''Transdermal''' refers to the method of delivering medication through the skin. This method is used to provide a controlled release of medication into the bloodstream over a period of time. Transdermal delivery systems are often used for medications that require steady blood levels and are an alternative to oral or injectable routes.
-A '''transdermal patch''' is adhered to the skin to deliver medication into the bloodstream. It is a viable alternative to oral administration because it helps to avoid the first pass metabolism. The rate of absorption is dependent on a number of factors, including the skin's physical condition and the presence of hair.
-== Mechanism of action ==
+==Mechanism==
-The skin is a complex barrier to direct drug penetration, therefore, transdermal patches are designed to control the rate of drug delivery into the systemic circulation. The drug penetrates through the skin layers and into the bloodstream. The drug's molecular size, ionization and lipid solubility determine its ability to penetrate the skin.
+Transdermal drug delivery involves the application of a drug formulation onto the skin, where it is absorbed into the bloodstream. The skin acts as a barrier, and the drug must penetrate the outer layer, the [[stratum corneum]], to reach the systemic circulation. This is achieved through the use of [[transdermal patch]]es, which are designed to adhere to the skin and release the drug at a controlled rate.
-== Advantages and disadvantages ==
+==Advantages==
-Transdermal administration has several advantages over oral administration. It provides a controlled release of the medication into the patient, usually through a porous membrane covering a reservoir of medication. It eliminates the need for multiple daily doses, improving patient compliance. However, the main disadvantage is that the skin is a very effective barrier and only medications with very specific properties can be absorbed through the skin.
+Transdermal delivery offers several advantages over other routes of administration:
+* **Avoidance of the gastrointestinal tract**: This method bypasses the digestive system, reducing the risk of gastrointestinal side effects and drug degradation by stomach acids.
+* **Improved patient compliance**: Transdermal patches are easy to apply and can be worn for extended periods, reducing the frequency of dosing.
+* **Controlled release**: The delivery system can be designed to release the drug at a constant rate, maintaining steady blood levels.
-== See also ==
+==Disadvantages==
+Despite its benefits, transdermal delivery also has limitations:
+* **Skin irritation**: Some patients may experience irritation or allergic reactions at the site of application.
+* **Limited drug types**: Only drugs that are potent and have suitable molecular properties can be effectively delivered transdermally.
+* **Variable absorption**: Factors such as skin condition, age, and site of application can affect drug absorption.
+==Applications==
+Transdermal patches are used for a variety of medications, including:
+* [[Nicotine replacement therapy]] for smoking cessation.
+* [[Hormone replacement therapy]], such as estrogen patches.
+* [[Pain management]] with opioid patches like fentanyl.
+* [[Cardiovascular disease]] treatment with nitroglycerin patches.
+==History==
+The concept of transdermal drug delivery has been around for centuries, with early examples including the use of herbal poultices. Modern transdermal patches were developed in the 1970s, with the first FDA-approved patch being a scopolamine patch for motion sickness in 1979.
+==Research and development==
+Ongoing research in transdermal delivery focuses on improving patch technology, enhancing drug penetration, and expanding the range of drugs that can be delivered transdermally. Innovations include microneedle patches and iontophoresis, which use electrical currents to enhance drug delivery.
+==Related pages==
+* [[Drug delivery]]
 * [[Pharmacokinetics]]
-* [[Route of administration]]
+* [[Topical medication]]
-* [[Drug delivery]]
+==References==
+{{Reflist}}
+[[Category:Drug delivery devices]]
 [[Category:Pharmacology]]
-[[Category:Drug delivery devices]]
 [[Category:Medical treatments]]
-{{stub}}
+[[File:Applying_transdermal_patch.jpg|thumb|right|A person applying a transdermal patch.]]