Tirosint is a liquid gel cap form of levothyroxine that has been on the market since 2011.
Monitoring
TSH levels are monitored to help optimize the dose of T4.
TSH stimulates the thyroid gland to make thyroid hormones.
Verywell / Jessica Olah
When hypothyroidism is adequately treated, TSH levels typically drop back down into the normal range.
So, a mainstay in determining the best dose of T4 ismeasuring TSH levels.
That is why TSH levels are generally measured six weeks after treatment has begun.
This process is continued until the TSH level reaches the desired range and symptoms are resolved.
T4 is converted to T3 in the tissues as needed.
And T3 is the thyroid hormone that does all the work.
Calculation of appropriate doses of T3 is trickier than appropriately dosing T4.
T4 is inactive, so if you take too much there is no immediate direct tissue effect.
T3 is a different story, though, as it is the active thyroid hormone.
Levothyroxine is the treatment of choice for congenital hypothyroidism.
Often, a liquid form of levothyroxine is given to infants.
If levels remain normal, transient hypothyroidism is the presumed diagnosis.
If levels become abnormal, permanent hypothyroidism is diagnosed.
The traditional reference range used by the healthcare provider to diagnose and manage hypothyroidism is significantly narrower in pregnancy.
Treating an underactive thyroid is a complex process that requires careful symptom and dose monitoring by a practitioner.
You will have to take these medications for the rest of your life.
Mincer DL, Jialal I.Hashimoto thyroiditis.
In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing.
McAninch EA, Bianco AC.The history and future of treatment of hypothyroidism[published correction appears inAnn Intern Med.
2016 Mar 1;164(5):376].Ann Intern Med.
2016;164(1):5056. doi:10.7326/M15-1799
Eghtedari B, Correa R.Levothyroxine.
In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing.
Benvenga S, Carle A.Levothyroxine formulations: pharmacological and clinical implications of generic substitution.Adv Ther.
2012;6:111. doi:10.2147/DDDT.S12894
Kim MI.Hypothyroidism in older adults.
In: Feingold KR, Anawalt B, Boyce A, et al., editors.
Endotext [Internet].
Pirahanchi Y, Jialal I.Physiology, thyroid stimulating hormone.
In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing.
Published 2018 Jan 17. doi:10.1186/s13044-018-0045-x
Toft AD, Beckett GJ.Thyroid function tests and hypothyroidism.BMJ.
combination therapy.Front Endocrinol (Lausanne).
2013;98(5):19821990. doi:10.1210/jc.2012-4107
Segni M.Congenital hypothyroidism.
In: Feingold KR, Anawalt B, Boyce A, et al., editors.
Endotext [Internet].
Segni M.Disorders of the thyroid gland in infancy, childhood and adolescence.
In: Feingold KR, Anawalt B, Boyce A, et al., editors.
Endotext [Internet].
2017 Sep;27(9):1212].Thyroid.
2017;27(3):315389. doi:10.1089/thy.2016.0457
Okosieme OE, Lazarus JH.Hypothyroidism in pregnancy.
In: Feingold KR, Anawalt B, Boyce A, et al., editors.
Endotext [Internet].
American Thyroid Association.Complementary and alternative medicine in thyroid disease (CAM).
Ross DS.Treatment of primary hypothyroidism in adults.
Cooper DS, Mulder JE, eds.
Waltham, MA: UpToDate Inc.
