About Thyrotoxic Periodic Paralysis (TPP)

TPP is most common amongst Asian populations
on Tue 6 Jun


A rare complication of hyperthyroidism (usually Graves’ disease), thyrotoxic periodic paralysis (TPP) was originally identified in in 1902 and has found to be most common amongst Asian populations who experience a 2% incidence of TPP in hyperthyroid patients as compared to 0.2% in non-Asian populations.


95% of cases occur in men.


The two main features of TPP are acute reversible episodes of muscle weakness lasting from a few hours to 3 days and decreased potassium levels in the blood (hypokalaemia). These conditions are connected as potassium is an important electrolyte for muscle and nerve functioning and in TPP the lower the potassium level the more severe the weakness.


In 80% of cases the first episode of TPP occurs between the age of 20-40 with a higher frequency of attack seen at night or early morning.  There is also a seasonal variation with attacks more frequent in the summer months.


Commonly reported factors which precede attacks include high carbohydrate ingestion and strenuous exercise but also:


  • Trauma
  • Acute upper respiratory tract infection
  • High salt diet
  • Emotional stress
  • Alcohol ingestion
  • Use of drugs such as corticosteroids and non-steroidal anti-inflammatory drugs



This is tricky as the initial symptoms of thyroid overactivity can be subtle and may precede the onset of the acute attack of TPP by months.  They include:


  • Weight loss
  • Palpitations
  • Heat intolerance
  • Increased appetite
  • Agitation
  • Insomnia
  • Hand tremors
  • A fast heart rate
  • Excessive sweating


The attack itself normally begins with muscle pain, cramps or muscle stiffness followed by weakness which begins in the upper leg muscles and can progress to both arms and legs. The bladder and bowel is not affected. Although there is complete recovery between episodes of weakness, the attacks can reoccur with intervals varying in individuals to days, weeks or months. 


If the weakness involves muscles involved in swallowing or breathing this is a medical emergency and an ambulance should be called.


Diagnosis will depend both on the awareness of the condition and its association with thyrotoxicosis by the doctor, and a recognition of abnormalities in biochemical and ECG tests. There may also be a family history of the condition.


As several other conditions can result in low potassium levels it is important to differentiate the condition particularly to avoid too high a level of potassium replacement which will exacerbate the hypokalaemia. 


The use of simple, fast, and inexpensive tests of blood and urine electrolytes, and acid-base status may aid in differentiating such disorders as supporting thyroid function tests may not always be immediately available.


Initial Treatment

Emergency treatment is necessary as the muscle weakness can extend to the heart - leading to life threatening conditions.  Treatment doses of potassium chloride have to be minimised to avoid rebound rises in potassium levels and beta blockers can help to present the recurrence of hypokalaemia. Patients are also normally recommended to have a low carb low salt diet.


Ongoing Treatment

TPP responds well to treatment and taking beta blockers and avoiding factors which are known to precipitate attacks can minimise or even prevent attacks. Initially anti-thyroid drugs are required to reduce the elevated thyroid hormone levels. Early definitive management of the hyperthyroidism by radioiodine or thyroidectomy are recommended to avoid any future recurrence.


I hope you have found this helpful.



Although every effort is made to ensure that all health advice on this website is accurate and up to date it is for information purposes and should not replace a visit to your doctor or health care professional.

As the advice is general in nature rather than specific to individuals Dr Vanderpump cannot accept any liability for actions arising from its use nor can he be held responsible for the content of any pages referenced by an external link



acanthosis nigricans Acromegaly Addison's disease adolescent diabetes problems adolescent thyroid problems Adrenal crisis adrenal fatigue Adrenal glands Anovulation artificial pancreas Autoimmune Thyroiditis Bariatric Surgery blood glucose levels blood pressure breastfeeding CAH Charcot foot cholesterol CHT coffee cold and flu medications Conception Congenital adrenal hyperplasia congenital hypothyroidism Consultant Endocrinologist London coronavirus cortisol covid-19 Cushing's disease Cushing's syndrome Depression Diabetes diabetes and bone health diabetes and heart health diabetes and oral health diabetes and parkinsons diabetes and sexual dysfunction diabetes and skin conditions diabetes and thrush diabetes in China diabetes insipidus diabetes latest diabetic ketoacidosis diabetic neuropathy Diabetic prevalence diabetic retinopathy diet for diabetes diet for obesity Disability Act Down's Syndrome Dr Mark Vanderpump e-consulting endocrine system fertility folic acid Freestyle Libre frozen shoulder and thyroid Fruit sugars gestational diabetes Gigantism Glucose Monitoring Glucose Tolerance Test gluten free Goitre Graves Disease Graves Orbitopathy guthrie test hair loss Hashimoto's Disease healthcare services hearing loss Heart Disease heel prick test Hepatitis C Hormones - most important how to lose weight hyperparathyroidism Hypersecretion Hyperthyroidism hyperthyroidism and respiratory problems Hypocalcaemia Hypogonadism hypoparathyroidism hypophysitis Hyposecretion Hypothyroidism hypothyroidism and respiratory problems IFG IGT immunotherapy side effects Impaired Fasting Glucose Impaired Glucose Tolerance Insulin Resistance Iodine IR iron Labour and birth late onset hypogonadism Levothyroxine Long Covid losing weight Low testosterone Mark Vanderpump MEN1 MEN2 menopause metabolic syndrome mood changes morning sickness Multiple endocrine neoplasia neuroendocrine tumour neuropathy Obesity obstructive sleep apnoea older patients online doctor OSA Osteoporosis overactive thyroid ozempic Pancreas Pancreatic Cancer Pancreatic Diabetes parathyroid glands Patient Resources Patient Support Groups PCOS PCOS and acne PCOS and fertility PCOS and Insulin PCOS diet Phaeochromocytomas Pituitary Gland POF Polycystic Ovary Syndrome Post menopause thyroid problem Post pregnancy thyroid problem postnatal diabetes medication postnatal thyroid medication Prader-Willi Syndrome pre-eclampsia prediabetes pregnancy Pregnancy and Diabetes Pregnancy and Thyroid Disease Premature Ovarian Failure prolactinomas PTH puberty Radioactive Iodine RAI resistant hypertension semaglutide Sheehan's Syndrome Skin tags sleep and diabetes sleep and obesity soy Soya steroid dependent subacute thyroiditis T4 Tara Palmer Tomkinson testosterone Tetany The endocrine system Thyroid thyroid and menstruation thyroid cancer Thyroid disease in children thyroid nodules Thyroid Storm thyroid tests Thyroiditis Thyrotoxic Periodic Paralysis Thyroxine TSH levels TSH Testing tumours Type 1 diabetes Type 2 Diabetes Type 3 diabetes underactive thyroid Vitamin B complex Vitamin D Waist circumference weight gain weightloss

Please get in touch

Phone: 07565 978310

Contact form