Increase your Synthroid dose
Your TSH of 10.7 mIU/L while taking levothyroxine 150 µg daily indicates inadequate treatment, and you need a dose increase of 12.5-25 µg daily. 1
Immediate Action Steps
Increase your levothyroxine dose by 12.5-25 µg daily (to either 162.5 µg or 175 µg). The guideline-recommended approach for dose adjustments uses incremental changes in this range to achieve target TSH levels 1. With a TSH >10 mIU/L, you are significantly undertreated and require prompt adjustment.
Recheck TSH in 4-8 Weeks
After any dose adjustment, wait 4-8 weeks before rechecking your TSH 1. This allows sufficient time for the medication to reach steady-state levels and for TSH to plateau. Testing earlier may give misleading results.
Before Increasing Dose: Rule Out These Common Problems
Your elevated TSH despite a relatively high dose (150 µg) suggests potential issues beyond simple underdosing. Address these factors first:
Medication Timing and Absorption Issues
- Take levothyroxine 30-60 minutes before breakfast on an empty stomach with water only 1. Taking it with food significantly reduces absorption.
- Avoid these medications/supplements within 4 hours of your levothyroxine 1, 2:
- Iron supplements
- Calcium supplements
- Antacids
- Proton pump inhibitors (PPIs)
Non-Adherence (Most Common Cause)
Non-compliance is the most common reason for persistently elevated TSH in patients on high doses 1. Be honest with yourself about missed doses. If you frequently forget doses, consider weekly dosing as an alternative 1.
Medical Conditions Affecting Absorption
Consider evaluation for 3:
- Gastritis or H. pylori infection (24% of refractory cases)
- Celiac disease (2.5% of cases)
- Medications interfering with absorption (15.6% of cases)
Target TSH Range
Your goal TSH should be within the normal reference range (typically 0.4-4.12 mIU/L) 1. The most reliable therapeutic endpoint is the serum TSH value itself 1.
Special Considerations
If You Have Heart Disease
If you have coronary artery disease or are over 50-60 years old, dose increases should be more cautious (12.5 µg increments) with monitoring for chest pain, palpitations, or shortness of breath 1, 2.
If Problems Persist
If your TSH remains elevated after addressing absorption issues and confirming compliance, you may need:
- Levothyroxine absorption testing to differentiate true malabsorption from pseudo-malabsorption 3, 4
- Evaluation for interfering medications or medical conditions
- Consideration that you may need doses >200 µg/day, which occurs in some patients 1
Common Pitfall to Avoid
Do not accept a TSH of 10.7 mIU/L as adequate treatment. This level is associated with ongoing hypothyroidism and potential cardiovascular consequences. Treatment should normalize your TSH, not just lower it slightly 5.