Recognize the physical exam findings of hyperthyroidism! 

Skin: warm moist skin, pretibial myxedema(Graves disease), thyroid acropachy, clubbing (Graves)
Eyes: Lid lag, stare, Proptosis (Graves disease), extra-ocular impairment (Graves disease)
CV: arrhythmias (sinus tachycardia, atrial fibrillation), high output CHF
Neuro: fine tremor, hyperreflexia
Psych: anxiety, agitation, psychosis, depression, insomnia, mania
Thyroid: diffuse thyromegaly, thyroid bruit (specific for Graves)

See the Stanford 25 website on how to do a thyroid exam 

High radioactive iodine uptake on RAIU scan in hyperthyroidism (de novo synthesis of thyroid hormone) 

1)Graves disease-can also diagnose with TSI-high sensitivity/specificity
2)Toxic adenoma
3)Multinodular Toxic Goiter
4)Iodine deficiency (rare in the USA)

Low radioactive iodine uptake on RAIU scan in hyperthyroidism (inflammation and destruction of thyroid tissue with release of pre-formed hormone OR extra-thyroidal source of thyroid hormone)

1)Thyroiditis (subacute granulomatous thyroiditis (De Quervains), painless, post-partum, suppurative/infectious thyroiditis)
2)Exogenous thyroid hormone administration
3)Struma Ovarii
4)Drug induced (eg: Amiodarone)
5)IV contrast load

Treatment

-Methimazole and beta blockers (eg:Propranolol) for hyper-adrenergic symptoms
-AVOID radio-iodine ablation if Graves’ ophthalmopathy, as can worsen eye involvement but
-Monitor for risk of agranulocytosis and hepatotoxicity with Methimazole!

See picture below for symptoms of hyperthyroidism! (copyright Nursing Education Consultants Inc) *Note that hyperdefecation commonly occurs, not diarrhea.