Injection Site Guide
Interactive guide to injection sites for SubQ and IM injections. Click any site to see technique details, needle recommendations, and compound-specific guidance.
Abdomen
The most common SubQ injection site. Large surface area allows for easy site rotation. Avoid the 2-inch radius around the navel.
Injection Technique
Pinch a fold of skin. Insert needle at 45-90° depending on body fat. Inject slowly. Release the skin fold after removing the needle.
Recommended: 27-31g, ½" needle
Best For
Tips
- ·Rotate injection sites — don't inject in the same spot repeatedly
- ·Avoid areas with stretch marks, scars, or bruises
- ·The 2-inch rule around the navel prevents hitting the peritoneum
- ·Room temperature medication reduces injection site reactions
Why Site Rotation Matters
Injecting in the same spot repeatedly can cause lipohypertrophy (fat buildup under the skin), scar tissue, and reduced absorption. Rotating between 4-6 sites ensures consistent absorption and prevents tissue damage. A simple rotation pattern: Left abdomen → Right abdomen → Left thigh → Right thigh → Left deltoid → Right deltoid, then repeat.
Quick Reference
| Site | Route | Max Volume | Needle | Best For |
|---|---|---|---|---|
| Abdomen | SubQ | 1 mL | 27-31g, ½" | GLP-1, peptides, HCG |
| Thigh (lateral) | IM / SubQ | 3 mL (IM) | 22-25g, 1-1.5" | Testosterone, estradiol |
| Deltoid | IM / SubQ | 2 mL (IM) | 23-25g, 1" | GLP-1, small-volume T |
| Ventrogluteal | IM | 3 mL | 22-25g, 1-1.5" | Testosterone, oils |
| Love handles | SubQ | 1 mL | 27-31g, ½" | GLP-1, peptides |
Frequently Asked Questions
Does injection site affect absorption?+
Yes — different sites have different blood flow and fat layer thickness, which affects absorption rate. SubQ abdomen typically absorbs slightly faster than thigh. For most medications, the difference is clinically insignificant, but consistency matters — use the same general area for the same medication.
Can I inject testosterone subcutaneously?+
Yes — SubQ testosterone is increasingly used and supported by research showing comparable serum levels to IM. Use a smaller needle (27-31g) and inject into the abdomen, thigh, or love handles. Many TRT clinics now default to SubQ for patient comfort.
How do I reduce post-injection pain (PIP)?+
Warm the medication to body temperature before injecting. Use the Z-track technique. Inject slowly (10 seconds per mL). Apply gentle pressure after removing the needle. Rotate sites consistently. Higher concentration oils (>250mg/mL) tend to cause more PIP.
What's the Z-track technique?+
Pull the skin to one side before inserting the needle, inject the medication, wait 10 seconds, then release the skin. This creates a zigzag path that prevents medication from leaking back along the needle track. Especially useful for IM injections.
How far apart should injection sites be?+
At least 1 inch (2.5cm) from the previous injection in the same area. Most practitioners recommend using a different site entirely for each injection and not returning to the same area for at least 1-2 weeks.
Is it normal to bleed after injecting?+
A small amount of blood (a drop or two) is normal — you may have nicked a superficial blood vessel. Apply pressure with a cotton ball. If bleeding is significant or you aspirated blood during the injection, you may have hit a larger vessel — withdraw and try a different site.
Can I inject GLP-1 medications in the thigh?+
Yes — semaglutide (Ozempic/Wegovy) and tirzepatide (Mounjaro/Zepbound) can be injected in the abdomen, thigh, or upper arm. The pre-filled pens have short needles designed for SubQ injection at any of these sites.
Related Tools
Doseline provides informational tools only. It is not a medical device and does not provide medical advice. Always consult a qualified healthcare provider.
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