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Medications · Thyroid
Compounded T3/T4 Combinations
Custom-ratio thyroid hormone replacement.
What it does
What Compounded T3/T4 Combinations is and why doctors prescribe it.
Compounded T3/T4 combinations offer the prescribing doctor a custom-ratio thyroid hormone preparation when neither T4 monotherapy nor a standard desiccated thyroid product fits the patient's clinical picture. This is doctor-led and lab-monitored therapy, not a one-size product.
How it works
Mechanism in plain English.
By prescribing T3 and T4 together at a specific ratio, the doctor can match the patient's metabolic and symptom response more precisely than either monotherapy or commercial combination products. Some patients have impaired peripheral T4-to-T3 conversion and benefit from direct T3 supplementation alongside T4.
How long it's been studied
Research history.
Combination thyroid therapy has been used for decades. Research on T3/T4 combinations vs T4 monotherapy continues to evolve, with some studies showing benefit in select patient subgroups. Compounded combinations are dispensed under 503A.
Dosing
Clinical context for the prescribing doctor.
Doctor-prescribed. Combination ratios commonly fall in the 4:1 to 14:1 (T4:T3) range, with daily doses scaled to body weight and clinical response. Your doctor monitors TSH, free T3, free T4, and symptoms, adjusting both the ratio and total dose as needed.
This page is informational, not a dispensing aid. Compounded T3/T4 Combinations is dispensed only on a patient-specific prescription written by a licensed doctor for an identified patient. Compounded drugs are not FDA-approved and should not be evaluated using branded-drug trial data. Availability varies by state and prescribed medication.
How to access Compounded T3/T4 Combinations through RonanRx
Three paths.
Doctors can prescribe compounded Compounded T3/T4 Combinations for individual patients through RonanRx. Patients with a doctor can sign up to receive their prescription. Patients without a doctor can learn how the referral works.
Patient with a doctor
Sign up to receive your prescription.
If your doctor has already prescribed Compounded T3/T4 Combinations, sign up so we can prepare and ship your medication. The signup wizard collects intake and connects you to the prescribing workflow.
Patient without a doctor
Get referred by a partner clinic.
RonanRx prescribes through partner clinics — we don't initiate prescriptions on this site. Read how the referral process works and how to find a partner clinic in your state.