Accepted answer
Week 9 is day 63: on a four-week ladder that is week 1 of dose step 3, and — at the seven-day half-life this class runs on — 9 half-lives in. Steady state is about five half-lives, so day 35 is where the concentration stops climbing on its own. Day 63 is 4 weeks past it, which means the level is no longer the variable. That distinction is most of the question: at week 1 of a step, an effect that is still accumulating is indistinguishable from one that is not resolving unless you know which side of day 35 you are on. Local erythema is a site-and-technique observation before it is a drug observation. It should track where and how you injected rather than how many weeks you have been injecting, so the useful record is a rotation log rather than a week count. Dose decisions are made under supervision, and nothing here is medical advice.
The relevant point is that repeated reactions at the same site suggest technique or rotation rather than a reaction to the compound.
Immediate stinging is usually the injectate: cold solution, a preservative, or a hypotonic diluent. Room-temperature solution injected slowly removes most of it.
Local reaction versus infection
| Feature | Local reaction | Sterile abscess | Cellulitis |
|---|
| Onset | Hours to 2 days | Days | 1–4 days, progressive |
| Warmth | Absent or minimal | Mild | Marked |
| Expansion | Static or shrinking | Slow | Expanding |
| Texture | Firm, flat or raised | Fluctuant | Diffuse, indurated |
| Systemic features | None | None | Fever, malaise possible |
| Action | Observe, rotate site | Clinical review | Same-day clinical review |
On the detail: a delayed local reaction — erythema, induration and itch appearing hours later and settling over two to four days — is a local immune response and is the common benign pattern.
Lipohypertrophy from repeated injection into the same site is documented in large observational studies of injection practice and alters absorption.
Mark the edge with a pen and note the time. Expanding is the signal that matters.