A hypodermic needle is a manually operated medical device used in conjunction with a syringe to inject substances (such as medications or solutions) into the body or to withdraw fluids (such as blood). It is a subcutaneous needle that penetrates the skin and is typically designed as a sharp, hollow metal tube.
Hypodermic needles vary in bevel shape, gauge, diameter, and length, depending on their intended use. They are commonly used for rapid fluid administration, when oral intake is not possible (e.g., vomiting), or when drugs (like insulin) require subcutaneous absorption. They are also critical in research environments that require strict sterile conditions, such as during the inoculation of sterile substrates, significantly reducing the risk of contamination.
Why Hypodermic Needles Minimize Contamination:
The needle surface is extremely smooth, preventing airborne pathogens from adhering and transferring to the substrate.
The needle tip is exceptionally sharp, leaving a very small puncture, which reduces the chance of larger microorganisms contaminating the entry point.
Hypodermic needles are usually made of high-grade stainless steel, with beveled and sharpened tips for smooth, painless skin penetration.
Hypodermic Needle Sizes (Gauge Chart)
There are six commonly used hypodermic needle sizes:
26G x 1/2″ (0.45 x 12 mm) – Brown
25G x 5/8″ (0.5 x 16 mm) – Orange
22G x 1 1/4″ (0.7 x 30 mm) – Black
21G x 1 1/2″ (0.8 x 40 mm) – Green
20G x 1 1/2″ (0.9 x 40 mm) – Yellow
19G x 1 1/2″ (1.1 x 40 mm) – Cream
In clinical use, needle gauges typically range from 7G (largest) to 33G (smallest).
21G needles are the most commonly used for general blood collection
16G or 17G are preferred for blood donation, as they allow faster blood flow
Though reusable needles are still used in some scientific fields, single-use disposable needles are now standard in clinical medicine. These are attached to a syringe hub by press-fit or twist-lock mechanisms, usually in plastic or aluminum housings.
Who Uses Hypodermic Needles?
Hypodermic needles are commonly used by:
Healthcare professionals: doctors, nurses, dentists, pharmacists, phlebotomists, paramedics
Patients: e.g., individuals with type 1 diabetes who self-administer insulin multiple times a day
Patients with severe allergies or conditions like asthma may also use hypodermic needles for emergency medication delivery
Technical Specifications – Hypodermic Needle
Compliant with International Standard: EN ISO 7864
Cannula: High-quality stainless steel
Transparent Cap: Medical-grade PP (Polypropylene)
Needle Hub: Medical-grade PP with color coding
Wall Thickness: Available in ultra-thin wall or regular wall
Color Coding: In accordance with ISO 6009
Packaging: Blister pack made of medical-grade paper and transparent film
Sterilization Method: Ethylene Oxide (EO)
Additional Features:
Medical silicone-coated cannula for smoother insertion
Precision beveled tip for painless and easy skin penetration
Color-coded needle hub designed to meet international standards
Protective cap to maintain needle integrity until use
Individually sealed in medical-grade blister packaging for sterility
