Seven cards. Every number is the open textbook’s own: landmarks, needle gauge and length, angle and volume. This is study content, not a how-to for giving an injection. Follow your program’s skills lab and facility policy.
Card 1
Ventrogluteal site (gluteus medius and minimus)
What it is
The textbook calls it the safest intramuscular site for adults and children: the muscle is thickest here, there are no penetrating nerves or blood vessels, and the fat layer is thin. It is the one the text generally recommends for adult IM medications, and it is preferred for all oily and irritating solutions, at any age.
The facts
- Landmarks
- The text has the heel or palm placed on the greater trochanter with the thumb pointing toward the belly button, the index finger extended to the anterior superior iliac spine, and the middle finger spread back toward the iliac crest. The site is the “V” between the two fingers.
- Gauge
- 20 to 25 gauge for aqueous solutions; 18 to 21 gauge for viscous or oil-based solutions.
- Needle length
- Thin adult: 5/8 to 1 inch (16 to 25 mm). Average adult: 1 inch (25 mm). Adult over 70 kg: 1 to 1½ inches (25 to 38 mm). Children and infants need shorter needles, set by agency policy.
- Volume
- Up to 3 mL for an average adult; up to 1 mL for children.
Remember: Greater trochanter, anterior superior iliac spine, iliac crest: the “V” sits between the index and middle fingers.
Card 2
Vastus lateralis (anterolateral thigh)
What it is
A site commonly used for immunizations in infants and toddlers. The text says it is preferred for infants because the muscle is the most developed one at that age.
The facts
- Location
- The area runs from one hand’s breadth above the knee to one hand’s breadth below the greater trochanter. The site is the outer middle third of that area.
- Positioning
- The text describes lying flat with the knees slightly bent, or sitting, to help the person relax the muscle.
- Gauge
- 20 to 25 gauge for aqueous solutions; 18 to 21 gauge for oily or viscous medications; 22 to 25 gauge for children.
- Needle length
- 1 to 1½ inches (25 to 38 mm) for adults; shorter for children, per agency policy.
- Volume
- A maximum of 3 mL per injection in an adult.
Remember: Hand’s breadth above the knee, hand’s breadth below the greater trochanter, outer middle third.
Card 3
Deltoid
What it is
A triangular muscle of the upper arm, found by feeling for the acromion process. The text notes that vaccines may be given here, and that the ventrogluteal site is generally recommended for adult IM medications.
The facts
- Location
- The middle of the deltoid, about 1 to 2 inches (2.5 to 5 cm) below the acromion, or about three finger widths below it.
- Gauge
- 22 to 25 gauge for immunizations.
- Needle length
- Adult male 60 to 118 kg: 1 inch. Woman under 60 kg: 5/8 inch. Woman 60 to 90 kg: 1 inch. Woman over 90 kg: may need 1½ inches.
- Volume
- Generally a maximum of 1 mL per injection.
Remember: Acromion first, then about three finger widths down. The smallest volume of the IM sites: 1 mL.
Card 4
Dorsogluteal site: the one to avoid
What it is
The textbook says this site should be avoided because of the risk of sciatic nerve injury, which can cause partial or permanent paralysis of the leg. It is on the sheet so that the name and the reason are on your study list; the text gives no landmarks for it.
The facts
- Why it is avoided
- Risk of sciatic nerve injury, with possible partial or permanent leg paralysis.
- What the text prefers
- The ventrogluteal site for adult IM medications.
Remember: Dorsogluteal = sciatic nerve risk. Ventrogluteal = the safe gluteal choice.
Card 5
Subcutaneous sites
What it is
A subcutaneous injection goes into the fat layer just under the skin, the adipose tissue below the dermis. The needle is shorter and finer than for IM, and the volume is smaller.
The facts
- Sites
- Outer lateral upper arm, abdomen, anterior upper thighs, upper back and the upper ventral gluteal area.
- The abdomen
- From below the costal margin to the iliac crest, and more than two inches from the umbilicus.
- Gauge and length
- 25 to 31 gauge, ½ inch to ⅝ inch. The text says to choose the length by the amount of subcutaneous tissue.
- Angle
- 45 or 90 degrees. 90 degrees for normal-sized or obese adults; 45 degrees for thin people or those with less adipose tissue at the site.
- Volume
- No more than 1 mL for adults and 0.5 mL for children.
- Site rotation
- Large surface areas allow rotating within the same site. The text says to avoid skin that is bruised, open or scarred, or over bony prominences, and that a condition impairing blood flow to an area, such as cellulitis, rules it out.
Remember: Fat layer, not muscle: 25 to 31 gauge, ½ to ⅝ inch, 1 mL at most, 45 or 90 degrees by how much fat there is.
Card 6
Intradermal sites
What it is
An intradermal injection goes into the dermis, just below the epidermis. It is the shallowest of the three routes, so the angle is nearly flat to the skin.
The facts
- Sites
- The most common sites are the inner surface of the forearm and the upper back below the scapula. The site should be free of lesions, rashes, moles or scars.
- Angle
- 5 to 15 degrees, bevel up.
- The bleb
- A small blister, called a bleb, should appear under the skin. The text says its presence indicates that the medication has been correctly placed in the dermis.
Remember: Shallowest route, flattest angle (5 to 15 degrees), and the bleb is the sign of dermis.
Card 7
The Z-track method
What it is
A technique the textbook describes for intramuscular injections. Its purpose, as the text gives it, is to prevent leakage of medication into the subcutaneous tissue, keep the medication in the muscle, and minimize irritation.
The facts
- The idea
- The skin is pulled about 1 inch (2 cm) to one side before the needle goes in, so that when the skin is released the path of the needle is no longer a straight line. That offset is the “Z”.
- The wait
- The text has the needle left in place for 10 seconds after the dose, then withdrawn smoothly with the skin released.
- Angle
- IM injections go in at a 90-degree angle.
Remember: Z-track: skin shifted about 1 inch (2 cm), 10 seconds before withdrawal, medication stays in the muscle.