E05.91 – Thyrotoxicosis, unspecified with thyrotoxic crisis or storm
ICD-10-CM 2027 diagnosis code · Disorders of thyroid gland
ICD-10-CM code
E05.91
- Code
E05.91(claims format:E0591)- Description
- Thyrotoxicosis, unspecified with thyrotoxic crisis or storm
- Billable
- Yes – valid for HIPAA-covered transactions
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 4. Endocrine, nutritional and metabolic diseases (E00-E89)
- Block
- E00-E07 Disorders of thyroid gland
- Parent codes
- E05 › E05.9
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
E05 – Thyrotoxicosis [hyperthyroidism]
Excludes1 (not coded here):
E05.9 – Thyrotoxicosis, unspecified
Applicable to:
- Hyperthyroidism NOS
Index terms for E05.91
Entries in the ICD-10-CM alphabetic index that lead to this code:
- Hyperthyroidism, with, storm
- Myxedema, localized, with storm
- Thyrotoxicosis, with, thyroid storm
- Myxedema, circumscribed, with storm
- Myocardiopathy, thyrotoxic, with storm
- Thyrotoxicosis, heart, with thyroid storm
- Cardiomyopathy, thyrotoxic, with thyroid storm
- Myopathy, in, thyrotoxicosis, with thyroid storm
- Chloasma, eyelid, hyperthyroid, with thyroid storm
- Disease, diseased, thyroid, heart, with thyroid storm
- Disease, diseased, heart, thyrotoxic, with thyroid storm
- Thyrotoxic, heart disease or failure, with thyroid storm
- Cardiomyopathy, metabolic, thyrotoxic, with thyroid storm
- Disease, diseased, heart, hyperthyroid, with thyroid storm
- Myasthenia, syndrome, in, thyrotoxicosis, with thyroid storm
- Syndrome, myasthenic, in, thyrotoxicosis, with thyroid storm
- Neuropathy, neuropathic, peripheral, autonomic, in, hyperthyroidism, with thyroid storm
- Failure, failed, Note: heart failure stages A, B, C, and D are based on the American College of Cardiology and American Heart Association stages of heart failure, which complement and should not be confused with the New York Heart Association Classification of Heart Failure, into Class I, Class II, Class III, and Class IV, thyrotoxic, with, thyroid storm
Related codes in E05.9
Frequently asked questions
What is ICD-10 code E05.91?
E05.91 is the ICD-10-CM code for thyrotoxicosis, unspecified with thyrotoxic crisis or storm, in the block E00-E07 (Disorders of thyroid gland).
Is E05.91 a billable code?
Yes. E05.91 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.
What category does E05.91 belong to?
It belongs to category E05 – Thyrotoxicosis [hyperthyroidism].
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.