ICD 10 Codes Guide - Healthcare

Hypothyroidism ICD 10

In this topic let us learn about Hypothyroidism, Types of Hypothyroidism, and Hypothyroidism ICD 10 codes along with descriptions & examples.


Hypothyroidism is a disorder of deficiency (hypo means deficiency) of thyroid hormone (produced by thyroid gland). This is more common in women than men and that too mostly older than 60 years.

Thyroid hormone is responsible to give energy to other organs. It controls metabolic rate, controls heart, muscle and digestive function, brain development and bone maintenance. So, deficiency of this hormone affects all the above processes.

Types of Hypothyroidism:

Selecting more specific code for hypothyroidism needs to have knowledge of types of hypothyroidism. These types are according to the reasons behind underactivity of thyroid gland.

Congenital – Present at birth.

Acquired or Primary– Most common cause is due to autoimmune disease Hashimoto’s thyroiditis. Immune system attacks thyroid and makes it difficult to produce hormone.

Other reasons are surgical removal of part or all of the thyroid gland and radiation of thyroid gland.

Secondary–Problem with another gland interferes activity of thyroid gland. For example, hormone produced by pituitary gland triggers the production of thyroid hormone. So, if any problem happens with pituitary gland it affects thyroid hormone production.

Severe–This is so called because the symptoms are more severe, even coma may occur.Patient can go to myxedema stage due to very low level of thyroid hormone.

Mild or subclinical –It is called subclinical because only the serum level of thyroid stimulating hormone from pituitary gland is slightly above normal. The thyroid hormones produced by the thyroid gland are still within normal range. This is less serious condition.

How to diagnose hypothyroidism?

Diagnosis can be made by identifying the symptoms and doing blood test. Symptoms caused by hypothyroidism are extremely high fatigue, cold sensitivity, constipation, dry skin and unexplained weight gain.

Lab tests used to confirm the diagnosis are levels of TSH (thyroid stimulating hormone) and thyroid hormone (thyroxine-T4) in blood.

Hypothyroidism ICD 10 Codes along with description:

Location in ICD 10 CM manual – Chapter 4, Endocrine, Nutritional and metabolic diseases (E00-E89)

Hypothyroidism ICD 10 Codes Description 
E03.0 -Congenital hypothyroidism with diffuse goiter

-Congenital parenchymatous goiter (nontoxic)

-Congenital goiter (nontoxic) NOS

E03.1 -Congenital hypothyroidism without goiter-Aplasia of thyroid (with myxedema)-Congenital atrophy of thyroid-Congenital hypothyroidism NOS
E03.2 -Hypothyroidism due-to-medications and other exogenous-substances-Drug induced hypothyroidism-Iatrogenic hypothyroidism
E03.3 -Post-infectious hypothyroidism
E03.4 -Atrophy of thyroid (acquired)
E03.5 -Myxedema coma
E03.8 -Other specified hypothyroidism

-Central hypothyroidism

-Hypothyroidism due to thyroiditis

-Hypothyroidism of prematurity

-Hypothyroidism, secondary

-Hypothyroxinemia of prematurity

-Tertiary hypothyroidism

E03.9 -Hypothyroidism, unspecified

-Myxedema NOS

E89.0 -Postprocedural hypothyroidism
P72.2 -Transitory neonatal hypothyroidism
E02 -Subclinical iodine deficiency hypothyroidism
E01.8 -Acquired iodine-deficiency hypothyroidism NOS

Note : Myxedema – Severe hypothyroidism

Hypothyroidism ICD 10 Example 1:

Olga, 50 year old housewife visits clinic with complaints of weight gain of 20 pounds in a year, fatigue, constipation, dry skin and cold intolerance.

Physical examination noted vitals which includes temperature 96.8 F, pulse 58/min, BP 140/100. She is moderately obese, has puffy face with pale, cool, dry and thick skin. The thyroid gland is slightly enlarged, not mobile.

Lab tests like CBC and differential WBC were normal, TSH is 23.0uU/ml, T4 concentration is 3.8 ug/dl

Assessment documented as “primary hypothyroidism”

Report following Hypothyroidism ICD-10 Codes:

  • E03.9 – Hypothyroidism, unspecified
  • E66.9 – Obesity, NOS

Note : As the cause of the disease is not mentioned correct code would be unspecified hypothyroidism.

Hypothyroidism ICD 10 Example 2:

65 year old woman came to clinic with her daughter for a routine check-up. Her PMH includes diabetes, hyperlipidaemia and hypertension. She states that she feels weaker nowadays. Her medication list was reviewed and which includes fish oil, atenolol, metformin and vitamin D. She has a surgical history of partial thyroidectomy due to goiter.

Vitals noted as temperature 97.1 F, pulse 82/min, BP 170/100. She is moderately obese, 3+ leg edema, no increased jugular venous pressure.

In the lab tests done today TSH noted 10.0 mU/L, T4 concentration is 3.0 ug/dl

Final clinical impression was mentioned as hypothyroidism due to thyroidectomy

Report following Hypothyroidism ICD-10 Codes:

  • E89.0 – Post procedural hypothyroidism
  • E66.9 – Obesity, NOS

Note: E89.0 can only be used if the Physician is clearly mentioning the hypothyroidism is due to surgery or radiation. We cannot assume that the hypothyroidism is due to thyroidectomy just because it is documented in surgical history.