Rapidly Dissolving Microneedles Incorporating Lidocaine Hydrochloride: A PVP/PVA-Based Approach for Local Anesthesia

Area of Science:

• Pharmaceutical Technology
• Biomaterials Science
• Dermatology

Background:

• Lidocaine is a common local anesthetic.
• Current administration methods (injections, creams) have drawbacks like pain and slow onset.
• Need for improved local anesthesia delivery systems.

Purpose of the Study:

• To develop dissolving microneedles for lidocaine hydrochloride delivery.
• To achieve rapid and convenient local anesthesia.
• To evaluate the performance of these microneedles.

Main Methods:

• Fabrication of six microneedle formulations using polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA).
• Evaluation of mechanical strength, skin insertion capability, drug release kinetics, and transdermal permeability.
• Ex vivo skin permeation studies to assess drug delivery efficiency.

Main Results:

• Successful fabrication of sharp, pyramidal microneedles.
• PVP-PVA blends yielded stronger microneedles compared to single polymers.
• Optimized formulation (F5) demonstrated high strength (>32 N), effective skin insertion, and rapid lidocaine release (>80% in 15 min).
• Ex vivo studies showed F5 delivered high lidocaine concentrations (>600 µg/mL in 15 min), significantly exceeding therapeutic levels and Emla cream.

Conclusions:

• Polyvinylpyrrolidone-polyvinyl alcohol microneedles are a viable platform for local anesthesia.
• This technology offers a promising alternative for painless and rapid anesthesia.
• Microneedles effectively combine advantages of injections and topical applications while mitigating their disadvantages.