it contains details about thyroid gland, functions, disorders and treatment.

1. THYROID DISORDERS
PRESENTED BY : PRATHYUSHA NASANA
16DU1R0040
ST ANN’S COLLEGE OF PHARMACY

2. CONTENTS
➢ INTRODUCTION
➢ REGULATION OF THYROID GLAND SECRECTIONS
➢ THYROID HARMONE SYNTHEIS
➢ DISORDERS OF THYROID GLAND
➢ DIAGNOSIS
➢ TREATMENT

3. THYROID GLAND
• One of the largest and highly vascularized endocrine gland in human body
• Butterfly shaped gland containing two lobes
• Lobus dexter(right)
• Lobus Sinister(left)
• located anteriorly above the trachea and just below the larynx
• Histologically, it is made up of follicular and para follicular cells
• Thyroid gland is controlled by hypothalamus and pituitary gland

4. IMAGE OFTHYROID GLAND

5. • Thyroid gland secretes three main hormones
• Thyroxine(T4)
• Tri-iodo thyronine(T3)
• Calcitonin
• T4 andT3 are produced by follicular cells of thyroid gland and are responsible for several
metabolic functions in body
• Calcitonin is produced by parafollicular cells and are responsible for calcium homeostasis

6. REGULATION OF THYROID GLAND SECRETIONS

7. THYROID HORMONE SYNTHESIS
• Iodide uptakeAnd its storage in Follicles
• Oxidation of iodine and iodination Of tyrosine to form monoiodotyrosine(MIT) and
diiodotyrosine(DIT)
• Coupling Of MIT and DIT leads toT3 orT4
• MIT+DIT---→T3
• DIT+DIT--→T4
• Thyroid peroxidase catalyses coupling
• Release of T3 andT4 into circulation
• Target tissues take upT3 from circulation for their metabolic needs except brain and pitutary
which take upT4 and convert it toT3 with their own cells.This conversion is carried out by
enzyme iodothyronine deiodinase

8. • These hormones have several functions in human body like
• Increasing the growth and development of body
• Increased metabolism(lipid,carbohydrate&protein)
• Increased body temperature(calorigenesis)
• T3 is 10x more active thanT4 and acts faster thanT4
• Only 20% of totalT3 is secreted by thyroid.Majority is formed from catalysis ofT4.
• Thus it may be concluded thatT3 is the active hormone,whileT4 is mainly a transportform;
functions as a prohormone ofT3.

9. DISEASES OF THYROID GLAND
~These fall into three main categories:
□Abnormal secretion of thyroid hormones(T3&T4)
◇Hyperthyroidism
◇Hypothyroidism
□Goitre – enlargement of thyroid gland
□Tumours

10. HYPERTHYROIDISM
• It is a condition resulting from increased levels of T4 andT3 but contain low levels of TSH
□Prevalance
• Females>Males
• Elder >children
□Causes
1. Graves disease
2. Nodular disease
3. Thyroiditis
4. Drug induced
ABNORMAL SECRETION OF THYROID HORMONES

11. 1.GRAVES DISEASE
• Auto immune disorder in which thyroid stimulating antibodies occupy theTSH receptors in the
thyroid gland,stimulate cell division and increase the production ofT3 andT4.
2.NODULAR DISEASES
• Toxic multinodular and single thyroid adenomas result in hyperthyroidism due to excessive
secretion of thyroid hormones by the tumours.
3.THYROIDITIS
• Inflammation of thyroid gland due to immune attack results in destruction of follicular cells of
thyroid gland and thus leading to leakage of stored thyroud hormone into blood stream.
4.DRUG INDUCED
• Drugs like lithium,iodide,amiodarone produce hyperthyroidism due to high iodine content in
them

12. SYMPTOMS
• Skin and appendages:inability to tolerate heat,warm and moist skin,sweating,hair
loss,protrusion of eyes.
• Cardiovasular:palpitations,tachycardia,increased pulse and systolic pressure,increased heart
rate and cardiac output
• Musculoskeletal:fatigue,tremors,weakness osteoporosis.
• Nervous system:insomnia,irritability,nervousness
• Gastrointestinal:diarrhoea,weightloss,increased apetite.

13. DIAGNOSIS
1. Increased levels ofT3 andT4 and decreased levels ofTSH
2. Thyroid scan- contain enlarged homogenous gland
3. Radioiodine uptake- uptake of iodine by thyroid gland is checked
TREATMENT
1. Anti thyroid drugs
2. Beta blockers
3. Radioactive iodine
4. surgery

14. • ANTI THYROID DRUGS
A.Thioamides:Propylthiouracil(PTU),Methimazole,carbimazole
• Inhibit production of thyroid peroxides
B.Ionic inhibitors:Potassium perchlorate
• Inhibit iodine binding
C.Iodides:KI solution
• inhibit hormone release
• BETA BLOCKERS: Propranolol,Atenolol
• RADIOACTIVE IODINE THERAPY: causes destruction of thyroid cells
• THYROIDECTOMY

15. •HYPOTHYROIDISM
• Precipitates due to low production of thyroid hormones by thyroid gland
•Women> Men
CLASSIFICATION
• Primary – thyroid failure
• Secondary – impairmentof pituitary gland,TSH deficit
• Tertiary – impairment of hypothalamus,TRH deficit
• Peripheral resistance to the action of thyroid hormone

16. AETIOLOGY
1. Cretinism
~hypothyroid condition occuring during foetal life or infants
~children are mentally retarded
~caused due to iodine deficiency,TSH receptor-blocking antibodies
2. Myxoedema
~found in young children and older people
~do not suffer from impaired mental function
~feature- accumulation of interstitial fluid on facial tissue
□Myxoedema coma- caused due to severe untreated hypothyroidism

17. 3.HASHIMOTO’STHYROIDOTIS
• Autoimmune disease in which body mistakes thyroud cells as foreign and attacks them resulting in
destruction of follicular cells and there by decreasing the production of thyroid hormones.
4.SUBACUTE THYROIDITIS
• Inflammation of thyroid gland occurs
• Due to inflammation,all stored thyroid hormones released into blood resulting in
hyperthyroidism,followed by reduced functioning of thyroid gland.
SYMPTOMS
• Skin appendages:dry,thickned,cool and produce flakes,puffy face and eyes,brittle nails,dry and coarse hair
• Nervous system: depression,fatigue,impaired cognitive abilities,tendon reflexes
• Gastrointestinal:weight gain,constipation,decreased apetite
• Cardiovascular:bradycardia,cardiac enlargement
• Presence of Goitre

18. TREATMENT
• Levothyroxine
• Liothyronine sodium
• Liotrix
• Dessicated thyroid
■LEVOTHYROXINE
• Synthetic product containing pure thyroxine
• Converted toT3 intracellularly
• Once dialy,half life: 7days

19. • Dosage
• Young,healthy- 50-100µg once dialy
• Adults-125µg once dialy
• Old patients- 25µg/day
• Preganant women requires high doses
■LIOTHYRONINE SODIUM
• Synthetic product containing pure form ofT3
• Used to restore normal levels ofTSH and totalT3
Demerits:rapid absorption & shorter half life
Cardiotoxicity
Frequency of dosing
Uses:Myxoedema,Myxoedema coma,patients undergoing thyroidectomy

20. ■LIOTRIX
• Combination product ofT4 andT3 in a ratio of 4:1
• Stable,potent and restores the normal values
• No longer recommended due to disadvantages
■DESICATEDTHYROID
• Natural preparation obtained from pork,beef,sheep
• Powder like substance containing 0.17-0.23% of iodine
• Demerits: prone to allergic reactions
storage affects potency
Posses problems associated withT3 preparations

21. GOITRE
• Enlargement of thyroid gland without signs of hyperthyroidism
• Caused by lack ofT3 andT4 and the low levels stimulate secretion ofTSH resulting in
hyperplasia of thyroid gland
• CAUSES
• Iodine deficiency
• Genetic abnormality affecting synthesis of T3 and T4
• Iatrogenic

22. TYPES
• Goitre may be nodular or diffuse
• Nodular goitre: uninodular or multinodular
• Uninodular goitre: one thyroid nodule
• Can be either inactive or active(toxic)
• Multinodular goitre: multiple nodules
• Diffuse goitre: the whole thyroid appearing to be enlarged due to
hyperpalsia
TREATMENT:treated according to cause.

23. TUMOURS OFTHYROID GLAND
• Malignant tumours are rare
• Benign tumours:
• Single adenomas are common and may become cysts
• Sometimes the adenoma secretes hormones and hyperthyroidism may develop
• Tumours become malignant,especially in the elders.
• Classification
• Papillary thyroid cancer
• Follicular thyroid cancer
• Medullary thyroid cancer
• Anaplastic thyroid cancer
• Treatment
• Thyroidectomy
• Radioactive iodine-131