How the projections actually work

myTSH uses a literature-derived pharmacokinetic model of levothyroxine absorption, distribution, and clearance, then fits a simple per-person adjustment using the dose/TSH/weight history you enter.

What you see is a forecast, not a prescription

• Input your recent doses, weight, and lab TSH values.
• The model estimates how much your TSH is likely to change per week at the current dose.
• You ask "what if I change the weekly dose by X µg?" — it shows the projected trajectory to your target.
• Uncertainty bands are shown because real biology + adherence + lab timing vary.

Important boundaries

This tool deliberately does not suggest a dose change for you. It only answers the question you pose. All clinical decisions remain between you and your physician.

Full methodology and references will live in the app (and future papers) once we have enough real longitudinal data. Early version — feedback welcome.