Bioidentical thyroid replacement therapy in practice: Delivering a physiologic T4:T3 ratio for improved patient outcomes with the Listecki-Snyder protocol.
Effective thyroid replacement therapy may be elusive to some patients, and compounding pharmacists have an opportunity to deliver more effective therapy. Goodman & Gilman's The Pharmacological Basis of Therapeutics 12th edition states that the body usually secretes T4:T3 in an 11:1 ratio but cautions against pursuing combined thyroid replacement due to the short halflife of T3 that necessitates multiple daily dosing; no commercial availability and lack of benefit were shown in trials. Commercial combinations of T4/T3 such as Armour Thyroid and Nature-Throid have a 4.22:1 T4:T3 ratio. Applying the same concept as bioidentical hormone replacement therapy, compounding pharmacists can deliver an 11:1 ratio using a commercial T4 product and taking into account oral bioavailability of each entity. The short half-life of T3 can be remedied by taking the patient's daily T3 dose and dividing it into two slow-release capsules to be dosed every 12 hours.
Midwestern University, Chicago College of Pharmacy, Downers Grove, Illinois, USA.
Scott
S
Snyder
Robert E
RE
Listecki
D001682:Biological Availability; D020249:Hormone Replacement Therapy; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000188:drug therapy*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000008:administration & dosage* / Q000493:pharmacokinetics; D016896:Treatment Outcome; D014284:Triiodothyronine / Q000008:administration & dosage* / Q000493:pharmacokinetics
D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine