Westhroid Shortage: What Providers and Prescribers Need to Know in 2026

Westhroid, the desiccated thyroid (NDT) brand manufactured by RLC Labs, has been effectively unavailable at most pharmacies since August 2020. For providers who have patients stabilized on Westhroid, this creates a genuine clinical management challenge. This guide summarizes the situation and provides a practical framework for managing affected patients.

Background: What Happened to Westhroid?

In August 2020, RLC Labs issued a voluntary nationwide recall of all unexpired lots of Nature-Throid and WP Thyroid following FDA testing that found sub-potent active ingredient content (T3/T4 as low as 87% of labeled amounts). Westhroid, manufactured at the same facility by the same company, has also been effectively unavailable since that time.

RLC Labs has been engaged in quality system remediation since the recall. As of 2026, no confirmed return to market date has been announced for any RLC Labs desiccated thyroid product. This situation has persisted for over five years, and clinicians should plan patient management accordingly.

Clinical Implications of the Sub-Potency Recall

Patients who were on Westhroid before the shortage may have experienced:

Return of hypothyroid symptoms (fatigue, weight gain, cognitive impairment, cold intolerance, constipation) on previous lots if sub-potency was present

Inconsistent lab results (elevated TSH, decreased free T4/T3) despite reported medication adherence

Difficulty finding consistent replacement therapy since the recall

The American Thyroid Association (ATA), American Association of Clinical Endocrinologists (AACE), and The Endocrine Society all recommend rechecking TSH levels after any switch to a new thyroid medication brand, as even small variations in active ingredient content can produce clinically significant changes.

Equivalent Alternatives for Patients on Westhroid

The following alternatives should be considered when transitioning patients off Westhroid:

Armour Thyroid

Armour Thyroid (AbbVie) is the most widely stocked NDT product and provides T3 + T4 in the same 1:4 USP ratio (9 mcg T3 : 38 mcg T4 per grain). Dose conversion from Westhroid to Armour Thyroid is approximately 1:1 by grain/milligram, but TSH monitoring at 4–6 weeks post-switch is essential due to differing inactive ingredients and manufacturing processes.

NP Thyroid

NP Thyroid (Acella Pharmaceuticals) is another widely available NDT option at a generally lower price point than Armour Thyroid. Contains the same active hormones per grain. Some patients prefer NP Thyroid due to its simpler inactive ingredient profile. Available at most major pharmacy chains.

Compounded Desiccated Thyroid

For patients with documented sensitivities to the inactive ingredients in commercial NDT brands, compounded desiccated thyroid from a PCAB-accredited compounding pharmacy may be appropriate. Compounded formulations can be customized to any dose increment and specific inactive ingredient profile. Providers should note that compounded NDT is typically not covered by insurance and involves patient out-of-pocket costs of $50–$120+ per month.

Synthetic T4 + T3 Combination Therapy

For patients who cannot access NDT, a synthetic combination of levothyroxine (T4) and liothyronine (T3) can approximate the dual-hormone profile of Westhroid. One grain of Westhroid contains 38 mcg T4 and 9 mcg T3. Clinical dosing should account for the higher potency of synthetic T3 compared to the T3 in NDT formulations.

Transition Protocol Recommendations

Obtain baseline TSH, free T4, and free T3 before transition

Begin new medication at the equivalent dose based on grain-to-grain conversion

Recheck TSH, free T4, and free T3 at 4–6 weeks

Titrate based on labs and symptom response

Counsel patients that different brands may feel different and reassure that adjustments are normal

Helping Patients Find Available Medications

When prescribing an alternative to Westhroid, your patients may still face difficulty finding the new prescription in stock—particularly Armour Thyroid, which has its own periodic availability fluctuations. medfinder for providers is a service that calls pharmacies on behalf of patients to locate available medication, reducing unnecessary follow-up calls to your office and helping patients get their prescriptions filled faster.

Patient Communication Guidance

Many Westhroid patients have strong brand loyalty and may be anxious or resistant about switching. Key talking points:

Validate their experience — the shortage is real and their frustration is understandable

Reassure that Armour Thyroid and NP Thyroid contain the same active hormones (T3+T4) in the same standard ratio

Explain that lab monitoring will ensure their dose is correct on the new brand

Offer an avenue to return to Westhroid if it becomes available again and they prefer it

For more guidance on helping your patients access their thyroid medication, see our provider guide to helping patients find Westhroid.