10.2 Parenteral Injections: Intradermal, Subcutaneous & Intramuscular (Z-Track)
Key Takeaways
- Needle gauge is inversely related to lumen diameter (e.g., 18G is large-bore, 27G is ultra-fine); syringe selection includes 1 mL tuberculin syringes (calibrated in 0.01 mL), insulin syringes (calibrated in units with orange caps), and standard 3 mL syringes.
- Intradermal (ID) injections use a 26–28G, 3/8 to 1/2-inch needle at a 10–15° angle (bevel UP) with 0.01–0.1 mL volume in the anterior forearm, creating a 6–10 mm wheal; Mantoux PPD tests are read at 48–72 hours by palpating induration.
- Subcutaneous (SC) injections deliver 0.5–1.5 mL at 45° (5/8-inch needle) or 90° (1/2-inch needle) into adipose tissue of the posterior arm, abdomen (>2 inches from umbilicus), or anterior thigh; heparin and insulin injection sites must never be massaged.
- Intramuscular (IM) injections use a 20–23G, 1 to 1.5-inch needle at 90° into the deltoid (max 1.0 mL), vastus lateralis (preferred in infants/toddlers <3 years; up to 2.0–3.0 mL), or ventrogluteal (safest adult site; up to 3.0 mL); the dorsogluteal site is strictly prohibited.
- The Z-track method is mandatory for irritating, viscous, or staining drugs (e.g., iron dextran), utilizing lateral skin displacement of 1–1.5 inches before 90° injection, a 10-second hold, and simultaneous needle withdrawal and tissue release without massage.
Last updated: August 2026
10.2 Parenteral Injections: Intradermal, Subcutaneous & Intramuscular (Z-Track)
Parenteral medication administration involves the delivery of therapeutic agents directly into body tissues or vascular spaces using a needle and syringe. Because parenteral administration bypasses the natural protective barriers of the skin, mucous membranes, and gastrointestinal digestive enzymes, absorption is rapid, complete, and irreversible.
Certified Medical Assistants perform parenteral injections across three primary non-vascular anatomical depths: Intradermal (ID), Subcutaneous (SC / SubQ), and Intramuscular (IM). Mastery of needle gauge and length selection, precise anatomical landmarking, aseptic injection protocols, and specialized methods such as the Z-track technique is essential to prevent severe complications, including neurovascular trauma, tissue necrosis, sterile abscesses, and medication failure.
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| PARENTERAL TISSUE LAYERS & INJECTION ANGLES |
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| |
| [ 10° - 15° ] [ 45° or 90° ] [ 90° ] |
| INTRADERMAL SUBCUTANEOUS INTRAMUSCULAR |
| | | | |
| +----+----+ +----+----+ +----+----+ |
| | Epidermis | | Epidermis | | Epidermis | |
| | Dermis <-- Wheal (Bleb) | Dermis | | Dermis | |
| +---------+ +---------+ +---------+ |
| | Subcutaneous Tissue | Subcutaneous Adipose <-- Bolus | Subcutaneous Tissue |
| +--------------------------+ +---------------------------------+ +-------------------------+ |
| | Muscle Tissue | Muscle Tissue | Muscle Belly <-- Deep Bolus |
| +--------------------------+ +---------------------------------+ +-------------------------+ |
+--------------------------------------------------------------------------------------------------+
1. Syringes, Needles & Aseptic Equipment Selection
Selecting the exact syringe, needle gauge, and needle length is governed by the prescribed injection route, medication viscosity, anatomical site, and patient body habitus.
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| CLINICAL SYRINGE TYPES & CALIBRATIONS |
+----------------------+--------------------+---------------------+--------------------------------+
| Syringe Type | Total Capacity | Scale Calibration | Primary Clinical Application |
+----------------------+--------------------+---------------------+--------------------------------+
| Tuberculin (TB) | 1.0 mL | 0.01 mL & minims | Intradermal PPD, allergy tests,|
| | | | pediatric micro-doses (<1 mL) |
+----------------------+--------------------+---------------------+--------------------------------+
| Insulin (U-100) | 100 Units (1.0 mL) | 1 Unit / 2 Units | U-100 regular & NPH insulin; |
| (Standard Orange Cap)| 50 U / 30 U Lo-Dose| 1 Unit increments | NEVER use for other medications|
+----------------------+--------------------+---------------------+--------------------------------+
| Standard Hypodermic | 3.0 mL | 0.1 mL increments | Routine IM & SubQ injections |
+----------------------+--------------------+---------------------+--------------------------------+
| Large Hypodermic | 5.0 mL to 10.0 mL | 0.2 mL increments | Reconstitution, irrigation, |
| | | | multi-mL deep IM loading doses |
+----------------------+--------------------+---------------------+--------------------------------+
Needle Anatomy & Dimensional Principles
A needle consists of five components: the hub (attaches to the syringe tip), shaft (elongated cannula), lumen (hollow internal bore), bevel (slanted angled opening at the tip), and point (sharpened distal apex).
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| THE INVERSE GAUGE RULE |
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| Needle GAUGE reflects the external diameter of the needle lumen. |
| GAUGE AND LUMEN DIAMETER ARE INVERSELY RELATED: |
| - SMALL GAUGE NUMBER = LARGE LUMEN DIAMETER (e.g., 18G bore = 1.27 mm; for viscous meds) |
| - LARGE GAUGE NUMBER = SMALL/FINE LUMEN DIAMETER (e.g., 27G bore = 0.41 mm; for ID/SubQ) |
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- Needle Length: Measured from the base of the hub to the needle point, ranging from 3/8 inch (short intradermal/subcutaneous) to 1.5–2.0 inches (deep intramuscular in large adults).
- Filter Needles (Safety Standard): When withdrawing medication from a glass ampule, the medical assistant must ALWAYS use a blunt filter needle or filter straw. The internal 5-micron filter traps microscopic glass shards generated during neck snapping. The filter needle must be removed and replaced with a standard safety injection needle before touching or injecting the patient.
- Needlestick Safety: Immediately activate the engineered needle safety mechanism (shield, hinged cover, or retraction) using a single-handed technique immediately after withdrawing the needle from tissue. Deposit immediately into an OSHA-approved rigid biohazard sharps container. NEVER manually recap a contaminated needle.
2. Intradermal (ID) Injections & Mantoux Tuberculin Testing
Intradermal injections deliver minute volumes into the vascular dermis directly beneath the epidermis. The dermis has a limited capillary blood supply, resulting in the slowest systemic absorption rate among all parenteral routes, making it ideal for diagnostic screenings and immunological allergy testing.
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| INTRADERMAL (ID) ROUTE SPECIFICATIONS |
+---------------------+----------------------------------------------------------------------------+
| Needle Gauge | 26 G to 28 G (fine bore) |
| Needle Length | 3/8 inch to 1/2 inch |
| Syringe Type | 1.0 mL Tuberculin (TB) syringe calibrated in 0.01 mL increments |
| Maximum Volume | 0.01 mL to 0.1 mL (standard diagnostic dose: exactly 0.1 mL) |
| Angle of Insertion | 10° to 15° (almost parallel to the skin surface) |
| Bevel Orientation | Strictly BEVEL UP |
| Primary Sites | Volar (anterior) forearm (3-4 fingerbreadths below antecubital space); |
| | Upper back below scapula (for extensive allergy testing panels) |
| Endpoint | Formation of a distinct, tense, pale WHEAL / BLEB (6 mm to 10 mm diameter) |
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Intradermal Injection Procedure
- Position the patient seated with the volar forearm resting comfortably on a flat surface, palm upward.
- Cleanse the anterior forearm with 70% isopropyl alcohol in an outward circular motion; allow to air dry completely.
- Hold the patient's forearm and stretch the skin taut with the non-dominant thumb.
- Position the syringe with the bevel facing strictly UP at a 10° to 15° angle to the skin.
- Insert the needle slowly until the bevel is completely covered beneath the epidermis (approximately 1/8 inch / 3 mm). The outline of the bevel should be visible translucent through the epidermis.
- Slowly inject the 0.1 mL solution. Resistance will be felt, and a tense, pale, elevated wheal (bleb) measuring 6 to 10 mm in diameter (resembling a mosquito bite) will immediately form.
- Withdraw the needle smoothly at the same angle and activate the safety device.
- CRITICAL POST-INJECTION CARE: Gently blot any minute drop of blood with sterile gauze. DO NOT MASSAGE, RUB, OR APPLY AN ADHESIVE BANDAGE with pressure over the site. Massaging or bandaging disperses the antigenic solution into the subcutaneous tissue, invalidating the test.
- If no wheal appears, or if the solution leaks out freely with immediate subcutaneous spreading, the needle was inserted too deeply into the subcutaneous layer; the test is invalid and must be repeated immediately on the opposite arm or at least 2 inches away.
Mantoux Tuberculin Skin Test (TST / PPD) Protocol
The Mantoux test utilizes 0.1 mL of Purified Protein Derivative (PPD) containing 5 Tuberculin Units (TU) to detect Mycobacterium tuberculosis cellular immune sensitivity.
- Reading Window: The patient must return to the clinic for test evaluation between 48 and 72 hours after injection. Results cannot be read before 48 hours or after 72 hours.
- Measurement Technique: Palpate the site across the forearm. Measure the transverse diameter of INDURATION (hard, raised, dense cellular swelling), NOT ERYTHEMA (redness). Measure the induration in millimeters (mm) using a calibrated flexible plastic ruler perpendicular to the long axis of the forearm. If no induration is felt, record as "0 mm".
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| CDC MANTOUX PPD INDURATION INTERPRETATION THRESHOLDS |
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| Induration Size | Target Patient Population / Diagnostic Interpretation |
+-------------------+------------------------------------------------------------------------------+
| ≥ 5 mm | POSITIVE in: |
| | - HIV-infected individuals |
| | - Recent close contacts of persons with infectious active tuberculosis |
| | - Patients with fibrotic chest radiograph changes consistent with prior TB |
| | - Organ transplant recipients & patients receiving systemic immunosuppression|
| | (e.g., equivalent of ≥15 mg/day prednisone for ≥1 month, TNF antagonists) |
+-------------------+------------------------------------------------------------------------------+
| ≥ 10 mm | POSITIVE in: |
| | - Healthcare personnel and clinical laboratory staff |
| | - Recent immigrants (<5 years) from high-prevalence TB nations |
| | - Injection drug users |
| | - Residents and employees of high-risk congregate settings (correctional |
| | facilities, nursing homes, homeless shelters, residential facilities) |
| | - Persons with clinical conditions (diabetes, chronic renal failure, silicosis)|
| | - Children <4 years of age or infants/adolescents exposed to high-risk adults|
+-------------------+------------------------------------------------------------------------------+
| ≥ 15 mm | POSITIVE in: |
| | - All persons with NO known risk factors or epidemiological risks for TB |
| | (general public screening) |
+-------------------+------------------------------------------------------------------------------+
3. Subcutaneous (SC / SubQ) Injections
Subcutaneous injections deposit medications into the loose adipose and connective tissue located beneath the dermis and above the muscular fascia. Because adipose tissue contains fewer blood vessels than skeletal muscle, subcutaneous absorption is sustained, uniform, and slower than intramuscular delivery.
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| SUBCUTANEOUS (SC) ROUTE SPECIFICATIONS |
+---------------------+----------------------------------------------------------------------------+
| Needle Gauge | 25 G to 27 G (or 29 G to 31 G for dedicated insulin pen needles) |
| Needle Length | 1/2 inch to 5/8 inch (3/8 inch for ultra-short insulin needles) |
| Maximum Volume | 0.5 mL to 1.5 mL in adults (maximum 0.5 mL in small children and infants) |
| Angle of Insertion | 45° for 5/8-inch needle (or lean/slender patients) |
| | 90° for 1/2-inch needle (or patients with abundant adipose tissue) |
| Primary Anatomical | 1. Outer posterior aspect of the upper arm (triceps region) |
| Sites | 2. Abdomen (anterior/lateral wall, at least 2 inches away from umbilicus) |
| | 3. Anterior aspect of thighs (middle third) |
| | 4. Scapular area of upper back and upper ventrogluteal areas |
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Subcutaneous Administration Protocol
- Select and inspect anatomical site. For insulin and heparin, ensure site rotation.
- Cleanse skin with alcohol wipe and let dry.
- Pinch Technique: Gently pinch a 1-to-2-inch skin fold between the non-dominant thumb and forefinger to elevate adipose tissue away from underlying skeletal muscle.
- Insertion Angle Selection:
- If you can pinch 1 inch of tissue, insert a 5/8-inch needle at a 45-degree angle.
- If you can pinch 2 inches of tissue, insert a 1/2-inch needle at a 90-degree angle.
- Insert the needle smoothly and firmly in a swift, dart-like motion.
- Release the skin fold (or keep pinched in extremely emaciated patients), stabilize the syringe barrel, and inject the medication steadily.
- Withdraw the needle smoothly along the angle of insertion, activate the safety cover, and apply gentle pressure with a dry sterile gauze pad.
Critical Subcutaneous Safety Rules: Insulin & Anticoagulants
- Insulin Administration: The abdomen provides the fastest, most consistent absorption, followed by the arms, thighs, and buttocks. Rotate injection sites systematically within the same anatomical zone (spacing successive injections 1 inch apart) to prevent lipohypertrophy (fibro-fatty lumps that delay insulin absorption). NEVER massage insulin sites.
- Heparin & Low-Molecular-Weight Heparin (Enoxaparin / Lovenox):
- Inject strictly into the abdominal wall (anterolateral or posterolateral abdomen, at least 2 inches from the umbilicus and above the iliac crest).
- DO NOT EXPEL THE AIR BUBBLE from pre-filled enoxaparin manufacturer syringes. The air bubble acts as an "air lock" that clears the needle track and seals the drug in the subcutaneous space, preventing tracking to the skin.
- DO NOT ASPIRATE. (Aspiration is obsolete and causes hematomas).
- NEVER MASSAGE THE INJECTION SITE. Massaging causes severe subcutaneous capillary rupturing, extensive ecchymosis, and painful hematomas.
4. Intramuscular (IM) Injections & Anatomical Landmarks
Intramuscular injections deliver medications deep into the vascular beds of large skeletal muscle bellies. Skeletal muscle possesses a rich vascular supply, permitting rapid systemic absorption and the administration of larger liquid volumes and hypertonic or moderately irritating solutions.
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| INTRAMUSCULAR (IM) ROUTE SPECIFICATIONS |
+---------------------+----------------------------------------------------------------------------+
| Needle Gauge | 20 G to 23 G (22-25G for aqueous vaccines; 20-22G for viscous antibiotics) |
| Needle Length | 1 inch to 1.5 inches for average adults (5/8" infants, up to 2" for obese) |
| Angle of Insertion | Strictly 90° (perpendicular to the muscle surface) |
| Maximum Volumes | - Deltoid: Maximum 1.0 mL (0.5-1.0 mL standard) |
| | - Vastus Lateralis: 1.0-2.0 mL (pediatric) up to 3.0 mL (developed adult) |
| | - Ventrogluteal: Up to 3.0 mL in well-developed adults |
| Standard Technique | Spread skin taut flat; dart-like 90° insertion; inject at 10 seconds/mL; |
| | wait 10 seconds before withdrawal; apply gentle gauze pressure |
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| THE FOUR INTRAMUSCULAR INJECTION SITES |
+-----------------------+----------------------------------+---------------------------------------+
| Muscle Site | Exact Anatomical Landmarking | Clinical Usage & Volume Limits |
+-----------------------+----------------------------------+---------------------------------------+
| 1. Deltoid Muscle | 2 to 3 fingerbreadths below the | Preferred site for routine adult and |
| (Upper Arm) | acromion process; inverted | adolescent vaccines (Flu, COVID, Tdap)|
| | triangle base at fingerbreadths, | Max Volume: 1.0 mL. Avoid radial |
| | apex at level of axillary fold. | nerve and deep brachial artery. |
+-----------------------+----------------------------------+---------------------------------------+
| 2. Vastus Lateralis | Middle third of anterolateral | PREFERRED and SAFEST site for infants |
| (Thigh) | thigh between greater trochanter | and children <3 years of age. Large, |
| | of femur and lateral condyle. | well-developed; free of major nerves. |
| | | Max Volume: 1-2 mL child, 3 mL adult. |
+-----------------------+----------------------------------+---------------------------------------+
| 3. Ventrogluteal | Palm on greater trochanter; | SAFEST adult IM site for large volume |
| (Gluteus Medius & | index finger on ASIS; middle | (up to 3.0 mL) or viscous drugs. |
| Minimus) | finger along iliac crest forming | Deep muscle; completely free of major |
| | a 'V'; inject in center of 'V'. | nerves and large blood vessels. |
+-----------------------+----------------------------------+---------------------------------------+
| 4. Dorsogluteal | Upper outer quadrant of buttock. | STRICTLY PROHIBITED & RETIRED. |
| (PROHIBITED / | Historic site near sciatic nerve | High risk of sciatic nerve paralysis, |
| UNSAFE) | and superior gluteal artery. | vascular injury, and thick SubQ fat. |
+-----------------------+----------------------------------+---------------------------------------+
Deltoid Muscle Landmarking Protocol
- Fully expose the patient's shoulder and upper arm.
- Palpate the lower edge of the acromion process (the bony prominence of the shoulder girdle).
- Place 2 to 3 fingerbreadths (approximately 1 to 2 inches / 2.5 to 5.0 cm) horizontally below the acromion process.
- Form an inverted triangle: the base is the line below your fingers, and the apex aligns horizontally with the anterior axillary line (armpit crease).
- The injection site is located directly in the center of the inverted triangle.
- Safety Rationale: Landmarking avoids the radial nerve, circumflex humeral artery, brachial artery, and subacromial bursa.
Vastus Lateralis Landmarking Protocol
- Position the patient supine or seated with knee slightly flexed to relax the quadriceps muscle.
- Place one hand on the patient's greater trochanter (hip joint) and the other hand above the lateral femoral condyle (knee joint).
- Divide the vastus lateralis muscle between these two boundaries into vertical and horizontal thirds.
- The target injection zone is the middle third of the anterolateral thigh.
- Clinical Standard: This is the mandatory, gold-standard IM site for all infants and children under 3 years of age, as it represents the largest, most vascularized muscle group prior to independent walking.
Ventrogluteal Landmarking Protocol
- Position the patient in a lateral recumbent position (side-lying with upper knee flexed) or supine.
- Place the palm of your hand over the patient's greater trochanter (use your right hand for the patient's left hip, or your left hand for the patient's right hip).
- Point your index finger toward the anterior superior iliac spine (ASIS).
- Spread your middle finger posteriorly along the iliac crest toward the buttocks, creating a distinct "V"-shaped triangle.
- The exact injection target is the center of the "V" triangle.
- Safety Rationale: The ventrogluteal muscle (gluteus medius and minimus) is thick, deep, free of major blood vessels and large nerves, and separated by a thin subcutaneous layer, making it the safest adult IM site.
Dorsogluteal Site Prohibition
The traditional dorsogluteal site (upper outer buttocks) has been permanently retired and prohibited by the CDC, WHO, and national medical/nursing standards. Extensive anatomical research demonstrates that the sciatic nerve courses unpredictably through this region, resulting in cases of permanent foot drop and sciatic neuropathy. Furthermore, the dorsogluteal region contains a thick adipose layer, causing up to 85% of injections to fail to reach muscle tissue, resulting in sterile abscesses and delayed drug efficacy.
5. The Z-Track Method for IM Injections
The Z-track technique is a specialized intramuscular injection method designed to seal irritating, caustic, or staining medications deep within the skeletal muscle mass, preventing retrograde tracking along the needle path into the subcutaneous tissue and dermal layers.
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| THE Z-TRACK INJECTION MECHANISM |
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| [1] SKIN PULLED LATERALLY (1 - 1.5") [2] NEEDLE INSERTED 90° & INJECTED |
| Skin / SubQ ======> (Pulled) Skin / SubQ ======> |
| +-------------------------+ +-------------------------+ |
| | Subcutaneous Layer | | Subcutaneous Layer | | |
| +-------------------------+ +---------------------|---+ |
| | Muscle Layer (Target) | | Muscle Layer (Target| | |
| +-------------------------+ +---------------------+---+ |
| |
| [3] NEEDLE WITHDRAWN & TISSUE RELEASED |
| When tissue snaps back, the needle tracks in the SubQ and Muscle slip out of alignment, |
| forming a "Z-SHAPED" anatomical seal that traps the drug deep inside the muscle belly. |
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Indications for the Z-Track Method
- Iron Dextran (Infed) / Iron Sucrose: Highly staining solution that causes permanent, dark brown/black tattoo-like cutaneous discoloration if leaked into subcutaneous tissue.
- Viscous / Caustic Medications: Haloperidol decanoate, hydroxyzine (Vistaril), chlorpromazine, medroxyprogesterone, deep hormonal depot preparations that cause intense subcutaneous pain, sterile chemical abscesses, and fat necrosis.
Step-by-Step Z-Track Clinical Protocol
- Aseptic Preparation: Draw up the prescribed medication into the syringe using a filter needle if drawn from an ampule. Add a 0.2 mL air lock if specified by the drug manufacturer. Change to a fresh, sterile 20–22G, 1.5 to 2.0-inch needle prior to injection so no trace medication coats the outer needle shaft.
- Site Selection: Select a large, deep muscle belly—the ventrogluteal site is strongly preferred; the vastus lateralis is an acceptable alternative. Never use the deltoid for Z-track.
- Cleanse Site: Wipe skin with 70% alcohol and allow to air dry.
- Displace Tissue: Place the ulnar side or palm of your non-dominant hand firmly against the patient's skin next to the injection site. Pull the skin and subcutaneous tissue firmly 1.0 to 1.5 inches (2.5 to 3.8 cm) laterally or downward away from the injection site and hold it firmly in place.
- Perpendicular Insertion: While maintaining continuous tissue traction with the non-dominant hand, insert the needle with the dominant hand at a strict 90-degree angle deep into the muscle belly.
- Slow Injection: Inject the medication slowly at a rate of 10 seconds per mL to allow the muscle fibers to distend and absorb the fluid under low pressure.
- The 10-Second Wait: After the plunger is completely depressed, wait 10 seconds with the needle in place before withdrawal. This allows the injected liquid to disperse into surrounding muscle tissue.
- Simultaneous Withdrawal & Release: Smoothly withdraw the needle at the same 90-degree angle and SIMULTANEOUSLY release the retracted skin and subcutaneous tissue. As the displaced tissue snaps back into its natural anatomical position, the needle track in the subcutaneous layer slides out of alignment with the needle track in the muscle, creating an impenetrable zig-zag seal.
- Hemostasis: Apply gentle pressure with a sterile gauze pad. DO NOT MASSAGE THE INJECTION SITE. Massaging forces the irritating medication back up through the muscle fascia into the subcutaneous fat.
Comprehensive Injection Routes, Needle Specs & Anatomical Landmarks
| Route / Method | Needle Gauge | Needle Length | Angle | Max Volume | Primary Landmarks & Target Sites | Clinical Indications & Essential Rules |
|---|---|---|---|---|---|---|
| Intradermal (ID) | 26 G to 28 G | 3/8" to 1/2" | 10° to 15° | 0.1 mL | Anterior forearm (3-4 fingerbreadths below AC fossa); upper back | Bevel strictly UP; produce 6-10 mm wheal; do NOT massage or bandage; Mantoux PPD read at 48-72h |
| Subcutaneous (SC - 45°) | 25 G to 27 G | 5/8" | 45° | 0.5 to 1.5 mL | Outer posterior upper arm; anterior thigh; upper abdomen | Used for 1" pinched skin fold or lean patients; insulin, allergy extracts, MMR, Varicella |
| Subcutaneous (SC - 90°) | 25 G to 27 G | 1/2" | 90° | 0.5 to 1.5 mL | Abdomen (>2" from umbilicus); triceps; anterior lateral thigh | Used for 2" pinched skin fold; Heparin/Lovenox (do NOT expel bubble, do NOT aspirate, do NOT massage) |
| IM: Deltoid | 22 G to 25 G | 1" to 1.5" | 90° | 1.0 mL | 2-3 fingerbreadths below acromion process; center of inverted triangle | Adult/adolescent immunizations (Flu, COVID-19, Tdap); avoid radial nerve & brachial artery |
| IM: Vastus Lateralis | 22 G to 25 G | 5/8" to 1.25" | 90° | 1.0 to 3.0 mL | Middle third of anterolateral thigh between greater trochanter & knee | MANDATORY preferred site for infants and toddlers <3 years; safe, thick, free of major neurovascular bundles |
| IM: Ventrogluteal | 20 G to 23 G | 1.5" | 90° | 3.0 mL | Center of 'V' formed by index finger on ASIS and middle finger on iliac crest | Safest adult IM site for large volumes and viscous medications; thick muscle, minimal SubQ fat |
| IM: Z-Track Technique | 20 G to 22 G | 1.5" to 2.0" | 90° | 2.0 to 3.0 mL | Ventrogluteal or Vastus Lateralis (NEVER deltoid) | Pull skin 1-1.5" laterally; 10s wait; withdraw & release simultaneously; change needle after draw; NO massage; iron dextran |
Test Your Knowledge
A medical assistant administers a Mantoux tuberculin skin test (PPD) to a healthcare worker. At the 48-hour follow-up reading, which finding constitutes the correct clinical interpretation of a positive result?
A
B
C
D
Test Your Knowledge
Which intramuscular injection site is the mandatory, safest preferred choice for administering routine pediatric immunizations to a 6-month-old infant?
A
B
C
D
Test Your Knowledge
When administering an intramuscular injection of iron dextran using the Z-track technique, which procedural step is essential to ensure a proper anatomical seal?
A
B
C
D