TB-500 pin site irritation — is this a vendor issue or am I pinning wrong?

L
Joined 2026
11 posts
4/6/2026 · 456 views

Third pin of a TB cycle. Small red lump at the pin site, slightly warm, a bit itchy. Doesn't look infected — no spreading, no pus, no fever. But the same sites have been lumpy for 2-3 days after each pin.

BPC on the same schedule, same needles, same BAC water — never had this. TB-specific.

Dilution, vendor, or pin technique? Trying to narrow down.

5 Replies

T
Joined 2026
28 posts
4/7/2026

Seconded. The 1mL reconstitution on TB is a common cause of site lumps. Dilute more, pin more volume, problem usually disappears.

H
Joined 2025
212 posts
hexaclinicContributor
4/8/2026

Most likely the dilution. TB-500 is a higher-concentration pin by volume than BPC at typical reconstitution. If you reconstituted a 5mg vial with 1mL BAC, you're pinning dense peptide solution. Redo with 2mL BAC, pin 2x the volume for the same dose. Usually fixes the site reaction.

Q2 stack
  • CJC-1295 no DAC · 100 mcg · pre-bed · sub-Q
  • Ipamorelin · 200 mcg · pre-bed · sub-Q
  • BPC-157 · 500 mcg · 2x/day · sub-Q
S
Joined 2025
97 posts
4/8/2026

Also — TB does produce a mild local inflammatory response for some people independent of dilution. If re-diluting doesn't fix it within a pin or two, consider rotating to a different site region (flank vs abdomen) or slowing your push speed. Faster push = more local irritation.

Growth + recovery
  • CJC-1295 no DAC · 100 mcg · pre-bed · sub-Q
  • Ipamorelin · 200 mcg · pre-bed · sub-Q
  • BPC-157 · 250 mcg · 2x/day · sub-Q
L
Joined 2026
11 posts
4/10/2026

Re-dilution fixed it. 2mL BAC on the next vial, no lumps. Thanks.

T
Joined 2026
50 posts
17d ago

Yeah dilution is def the first move. TB is peptide-dense even at standard reconstitution and subq tissue gets angry with concentrated solutions. I'd go 2mL minimum and see if the lumps shrink within a pin or two. If they persist after that then yeah, consider it might just be how your body reacts to TB locally, some people get that regardless. The inflammation itself isn't dangerous but rotating injection sites and going slower on the plunge helps most people.

Tirze cycle
  • Tirzepatide · 5 mg · weekly · sub-Q
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