Increase Your Levothyroxine Dose Now
Your TSH of 11.5 mIU/L while taking levothyroxine 75 µg indicates inadequate treatment requiring immediate dose adjustment—increase to 87.5–100 µg daily and recheck thyroid function in 6–8 weeks. 1
Why Your Current Dose Is Insufficient
- TSH >10 mIU/L represents significant undertreatment that carries approximately 5% annual risk of progression to overt hypothyroidism and is associated with cardiac dysfunction, elevated LDL cholesterol, and reduced quality of life 1
- Your free T4 of 1.06 ng/dL (approximately 13.6 pmol/L) is within normal range, confirming this is subclinical hypothyroidism on inadequate replacement therapy rather than overt disease 1
- Treatment is mandatory at this TSH level regardless of symptoms—you don't need to feel bad to require adjustment 1
Exact Dose Adjustment Protocol
Recommended Increase
- Increase by 12.5–25 µg based on your current 75 µg dose 1
- For most patients under 70 without cardiac disease, a 25 µg increment to 100 µg daily is appropriate 1
- If you are over 70 or have heart disease, use the smaller 12.5 µg increment to 87.5 µg daily 1
Monitoring Timeline
- Recheck TSH and free T4 in exactly 6–8 weeks after the dose change—this is the time required to reach steady-state hormone levels 1
- Target TSH: 0.5–4.5 mIU/L with normal free T4 1
- Once stable, monitor TSH every 6–12 months or sooner if symptoms change 1
Symptoms to Monitor
Signs Your Dose Is Working (Improvement Expected in 6–8 Weeks)
- Energy level improvement—reduced fatigue is often the first benefit 1
- Weight stabilization—unexplained weight gain should stop 1
- Improved cold tolerance—feeling less cold than before 1
- Better bowel function—relief of constipation 1
- Cognitive clarity—reduced "brain fog" or mental slowing 1
Warning Signs of Overtreatment (Seek Medical Attention)
- Heart palpitations or rapid heartbeat (>100 bpm at rest) 1
- Chest pain or pressure—especially if you have cardiac disease 1
- Tremor or shakiness 1
- Heat intolerance or excessive sweating 1
- Unintentional weight loss 1
- Anxiety or insomnia 1
Critical Safety Considerations
Before Increasing Your Dose
- If you have cardiac disease, start with the smaller 12.5 µg increment to avoid unmasking cardiac ischemia or precipitating arrhythmias 1
- If you are over 70 years old, use 12.5 µg increments regardless of cardiac history 1
- Rule out adrenal insufficiency if you have unexplained hypotension, hyponatremia, or hyperpigmentation—starting thyroid hormone before treating adrenal insufficiency can trigger life-threatening adrenal crisis 1
Common Pitfalls to Avoid
- Never adjust your dose more frequently than every 6–8 weeks—changing doses before steady state leads to inappropriate adjustments 1
- Don't skip the follow-up testing—approximately 25% of patients on levothyroxine are unintentionally overtreated, increasing risks for atrial fibrillation, osteoporosis, and fractures 1
- Confirm the TSH elevation was persistent—30–60% of elevated TSH values normalize spontaneously, but since you're already on treatment, this dose adjustment is clearly needed 1
Why This TSH Level Matters
- TSH >10 mIU/L is associated with measurable cardiac dysfunction, including delayed myocardial relaxation, reduced cardiac output, and increased systemic vascular resistance 1
- Your cardiovascular risk is elevated through adverse effects on lipid metabolism (higher LDL cholesterol and triglycerides) 1
- Quality of life suffers even without obvious symptoms—fatigue, cognitive slowing, and metabolic dysfunction occur at this TSH level 1
Taking Your Medication Correctly
- Take levothyroxine on an empty stomach, 30–60 minutes before breakfast 1, 2
- Separate from iron, calcium supplements, or antacids by at least 4 hours 2
- Avoid soybean flour, cottonseed meal, walnuts, and high-fiber foods near dosing time—these bind levothyroxine and reduce absorption 2
- Grapefruit juice may delay absorption—avoid consuming it around medication time 2
Special Populations Requiring Modified Approach
If You Are Pregnant or Planning Pregnancy
- Increase your dose immediately and target TSH <2.5 mIU/L in the first trimester 1
- Pregnancy increases levothyroxine requirements by 25–50%—your current undertreatment poses risks for preeclampsia, low birth weight, and fetal neurodevelopmental effects 1, 2
If You Have Cardiac Disease
- Start with 87.5 µg (12.5 µg increase) and monitor closely for angina, palpitations, or worsening heart failure 1
- Obtain an ECG to screen for baseline arrhythmias before increasing the dose 1
If You Are Over 70 Years Old
- Use the smaller 12.5 µg increment to 87.5 µg daily 1
- Consider repeating testing within 2 weeks if you have atrial fibrillation or serious cardiac conditions rather than waiting the full 6–8 weeks 1
What Happens If You Don't Increase Your Dose
- Persistent TSH elevation >10 mIU/L carries 5% annual risk of progression to overt hypothyroidism 1
- Cardiovascular function remains impaired—delayed cardiac relaxation and abnormal output persist 1
- Lipid abnormalities continue—elevated LDL cholesterol and triglycerides increase cardiovascular risk 1
- Quality of life remains suboptimal—fatigue, weight issues, and cognitive slowing persist even if you don't recognize them as symptoms 1
Evidence Quality
- The recommendation to treat TSH >10 mIU/L with levothyroxine is supported by "fair" quality evidence from expert panels, reflecting consistent observational data and physiological rationale despite limitations in randomized controlled trial data 1
- Treatment at this TSH threshold is standard of care across major endocrinology societies 1