Abstract

Needle-free drug delivery was first proposed as early as the mid-19th century (1) and was demonstrated to work many decades ago with one of the first major patents filed by Lockhart in the 1930s (2). At first glance, it is a concept both highly attractive and very simple—accelerate a drug formulation (liquid, powder, or depot) so that it penetrates the skin without the requirement for a needle. This avoids a multitude of disadvantages that are inherent in needle use:

Risk of cross-contamination from needle-stick injury.

Under- or overdosing resulting in poor injection technique of patients.

Costs of sharps disposal.

Needlephobia (up to 15% of people are clinically needle-phobic, and most people are apprehensive about receiving injections).

Injection site pain.

Poor compliance leading to long-term worsening of conditions.

Increased costs due to patients visiting hospitals/physicians’ offices for injections.