Increase Your Levothyroxine Dose
Your TSH of 7.08 mIU/L on 175 mcg levothyroxine indicates inadequate replacement requiring a dose increase of 12.5–25 mcg. 1
Why Your Current Dose Is Insufficient
Your TSH is elevated above the target range of 0.5–4.5 mIU/L, confirming that 175 mcg is not providing adequate thyroid hormone replacement. 1 This level of TSH elevation (>7 mIU/L) carries approximately 5% annual risk of progression to overt hypothyroidism and is associated with adverse cardiovascular effects and abnormal lipid metabolism. 1
Recommended Dose Adjustment
Increase levothyroxine by 12.5–25 mcg based on your current dose and clinical characteristics. 1 For most patients on 175 mcg, a 25 mcg increment is appropriate. 1 If you are over 70 years old or have cardiac disease, use the smaller 12.5 mcg increment to avoid cardiac complications. 1
Monitoring After Dose Change
- Recheck TSH and free T4 in 6–8 weeks after the dose adjustment, as this represents the time needed to reach steady state. 1
- Target TSH should be 0.5–4.5 mIU/L with normal free T4 levels. 1
- Once stable, monitor TSH every 6–12 months or sooner if symptoms change. 1
Critical Factors That May Affect Your Dose
Before increasing the dose, verify that you are:
- Taking levothyroxine on an empty stomach, 30–60 minutes before breakfast, at least 4 hours apart from iron, calcium supplements, or antacids. 1
- Not experiencing malabsorption from conditions like celiac disease, gastritis, Helicobacter pylori infection, or inflammatory bowel disease, all of which reduce levothyroxine absorption. 2
- Not taking interfering medications such as proton pump inhibitors, bile acid sequestrants, or certain supplements that impair absorption. 2
If you have gastrointestinal symptoms or poor TSH control despite reported adherence, consider evaluation for malabsorption disorders. 2, 3
Common Pitfalls to Avoid
- Do not wait to increase the dose. A TSH >7 mIU/L requires adjustment regardless of symptoms. 1
- Avoid excessive dose increases that could lead to iatrogenic hyperthyroidism, which increases risk for atrial fibrillation, osteoporosis, and cardiac complications. 1
- Do not recheck TSH before 6–8 weeks, as adjusting doses too frequently before reaching steady state leads to inappropriate dosing. 1
- Never assume the problem is non-compliance without first ruling out malabsorption or medication interactions. 2
Special Considerations
If you have cardiac disease or are over 70 years old, start with a 12.5 mcg increase and monitor closely for angina, palpitations, or arrhythmias. 1 If you are planning pregnancy, more aggressive TSH normalization is warranted, targeting TSH <2.5 mIU/L in the first trimester. 1