Some NP Thyroid Lots Recalled Due to
Reduced Potency

Nancy A. Melville

May 03, 2021

In its third voluntary recall in the past year, Acella Pharmaceuticals has announced a nationwide recall of specific lots of its popular hypothyroid treatment NP Thyroid tablets USP, this time after routine testing found the pills to be subpotent.

Specifically, the affected lots were found to contain less than 90% of the drug's two labeled ingredients to treat hypothyroidism: liothyronine (LT3) and/or levothyroxine (LT4).

The affected lots include 15-mg, 30-mg, 60-mg, 90-mg and 120-mg formulations of NP Thyroid tablets, packed in 100-count and 7-count bottles.

The list of the specific recalled lots is published on the Food and Drug Administration website.

Acella reports that, so far, 43 reports of serious adverse events that could be related to the recall have been received.

Symptoms suggesting patients may have received a subpotent batch include the common signs of hypothyroidism, such as fatigue, increased sensitivity to cold, constipation, dry skin, puffy face, hair loss, slow heart rate, depression, swelling of the thyroid gland and/or unexplained weight gain or difficulty losing weight, Acella reports.

"There is reasonable risk of serious injury in newborn infants or pregnant women with hypothyroidism including early miscarriage, fetal hyperthyroidism, and/or impairments to fetal neural and skeletal development," the company cautions in the recall statement.

Acella adds that toxic cardiac manifestations of hyperthyroidism, including cardiac pain, palpitations or cardiac arrhythmia may occur in elderly patients and patients with underlying cardiac disease.

While Acella is notifying affected parties to discontinue distribution of the recalled products, it advises that patients who are currently taking NP Thyroid from the lots being recalled "should not discontinue use without contacting their healthcare provider for further guidance and/or a replacement prescription."

In November 2020, a recall of NP Thyroid was issued after FDA testing found subpotent levels, as low as 87% of the labeled amount, of LT4 in some lots.

And earlier, in May 2020, the company recalled 13 lots of the tablets due to excessive potency, with FDA testing showing some tablets contained up to 115% of the labeled amount of LT3.

NP Thyroid is a type of desiccated animal thyroid product that was long the standard of care for hypothyroidism prior to the advent of the synthetic hypothyroidism drug, Synthroid (levothyroxine sodium), now the most commonly used hypothyroidism treatment.

On its website, Acella refers to NP Thyroid as a "natural choice for thyroid therapy," as desiccated thyroid is commonly referred to.

However, one of the most common concerns about desiccated thyroid is a tendency to have unreliable concentrations of active ingredients, as discussed in American Thyroid Association recommendations.

The "amounts of both T4 and T3 can vary in every batch of desiccated thyroid, making it harder to keep blood levels right," the ATA states.

"Finally, even desiccated thyroid pills have chemicals (binders) in them to hold the pill together, so they are not completely 'natural.' "

Consumers with questions about the recall are advised to email Acella Pharmaceuticals at or call 1-888-424-4341, Monday through Friday from 8:00 am to 5:00 pm ET.

This article originally appeared on, part of the Medscape Professional Network.


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