Question

-Patient Guidan is on levothyroxine 0.150mcg PO daily every AM.

-A TSH was drawn prior to administration and the results showed: TSH-92 MIU/m....Normal is 0.4-4.0 MIU/m.

-You call the physician on this , Did the provider increase or decrease the levothyroxine dose and why?

Answer 1

The provider should increase the dose of levothyroxine because the TSH level is too high.

TSH is a pitutary secreted hormone which stimulates the thyroid gland to secrete T3,T4 hormone.Higher TSH means the patient has hypothyroidism.snd we give thyroid hormone supplements to balance the thyroid levels.According to the case the patient is on levothyroxine which is a artificial T4 hormone and it has a half life of 7-9 days which means doing a lab test before or after administration of the levothyroxine will not have any effect on the TSH values because it will take nearly 7 days for half of the drug to be cleared of from the body so it doesn't matter if you have not taken the medicine for one or two days before the blood collection .which tells us that the higher level of TSH for this patient is not a false report .and the patients really has a higher TSH of 92.so the physician will have to increase the dose of levothyroxine to maintain a balanced TSH level.

If the patient was on combination drugs like litothyronine the half life is only 18 hours which means the TSH will be suppressed immediately after taking the tablet .so then slowly increase to a steady state so a blood test should be done just before the medication else the TSH may be low which is a false positive report.