One-liner#

Recognize hyperthyroidism presenting as palpitations, tremor, weight loss, or heat intolerance; confirm with TSH/free T4; initiate beta-blocker for symptom control and refer to endocrinology for definitive management.

Quick nav#

• Red flags / send to ED
• Key history
• Focused exam
• Differential (quick pattern recognition)
• Workup
• Initial management
• Management by diagnosis
• Follow-up
• Patient instructions
• Smartphrase snippets

Red flags / send to ED#

• Thyroid storm: Fever >38.5°C + tachycardia (often >140) + altered mental status + hyperthyroid symptoms → call 911
• New atrial fibrillation with rapid ventricular response (HR >120 with symptoms) → ED for rate control
• Severe dehydration from vomiting/diarrhea with inability to tolerate PO → ED
• Acute psychosis or severe agitation → ED
• Heart failure symptoms (dyspnea at rest, orthopnea, edema) in setting of hyperthyroidism → ED

Thyroid storm triggers: Infection, surgery, trauma, iodine load (contrast), medication non-adherence, DKA

Key history#

Hypermetabolic symptoms:

• Weight loss despite normal or increased appetite
• Heat intolerance, excessive sweating
• Palpitations, racing heart
• Tremor (especially hands)
• Anxiety, irritability, emotional lability
• Insomnia, difficulty sleeping
• Fatigue (paradoxically common)

GI symptoms:

• Increased bowel frequency, loose stools
• Nausea, vomiting (severe = red flag)

Cardiovascular:

• Palpitations (most common presenting symptom)
• Dyspnea on exertion
• Chest discomfort

Neuromuscular:

• Proximal muscle weakness (difficulty climbing stairs, rising from chair)
• Fine tremor

Reproductive:

• Menstrual irregularities (oligomenorrhea, amenorrhea)
• Decreased libido
• Gynecomastia in men

Eye symptoms (Graves’ specific):

• Eye irritation, grittiness, tearing
• Double vision
• Proptosis (“eyes look bigger”)
• Eyelid retraction

Timeline and course:

• Onset: gradual (weeks to months) vs acute
• Prior thyroid disease or treatment
• Recent pregnancy (postpartum thyroiditis)
• Recent iodine exposure (contrast, amiodarone, supplements)

Medication review:

• Amiodarone (can cause hyper- or hypothyroidism)
• Lithium (usually hypothyroid, but can cause hyperthyroid)
• Levothyroxine (overreplacement)
• Biotin supplements (interferes with assays—false results)
• Iodine-containing supplements or kelp

Family history:

• Thyroid disease
• Autoimmune conditions

Focused exam#

Vital signs:

• Tachycardia (resting HR often >90)
• Widened pulse pressure
• Elevated systolic BP
• Low-grade fever (if severe)

General:

• Anxious, fidgety appearance
• Weight loss evident
• Warm, moist skin
• Fine hair texture

Thyroid exam:

• Size: diffuse enlargement (Graves’) vs nodular (toxic nodule/MNG)
• Tenderness: tender = thyroiditis; non-tender = Graves’/toxic nodule
• Bruit: vascular bruit over thyroid suggests Graves'
• Nodules: palpable nodule(s)

Eyes (Graves’ ophthalmopathy):

• Proptosis (exophthalmos)
• Lid lag (upper lid doesn’t follow downward gaze)
• Lid retraction (sclera visible above iris)
• Periorbital edema
• Conjunctival injection
• Extraocular movement limitation

Cardiovascular:

• Irregular rhythm (atrial fibrillation)
• Hyperdynamic precordium
• Flow murmur

Neurologic:

• Fine tremor (have patient extend hands, place paper on top)
• Hyperreflexia
• Proximal muscle weakness (have patient rise from squat)

Skin:

• Warm, moist, velvety
• Pretibial myxedema (Graves’ specific—rare)
• Onycholysis (nail separation from bed)

Extremities:

• Thyroid acropachy (clubbing—rare, Graves’ specific)

Differential (quick pattern recognition)#

Common/likely (outpatient)#

Can’t-miss / urgent#

Workup#

Initial labs (all suspected hyperthyroidism):

Second-tier labs (to determine etiology):

Imaging:

Other tests:

When NOT to order:

• RAIU scan in pregnancy (contraindicated)
• Extensive workup for mildly low TSH (0.1-0.4) with normal free T4—repeat in 6-8 weeks first
• TSI/TPO if diagnosis is clear and patient going to endocrinology anyway

Biotin interference: Biotin supplements (even in multivitamins) can cause falsely low TSH and falsely high free T4. Ask about supplements; hold biotin for 2-3 days before labs if concerned.

Initial management#

Symptomatic control (PCP can initiate):

• Beta-blocker for symptom relief (palpitations, tremor, anxiety)
• Start while awaiting endocrinology evaluation
• Propranolol or atenolol most commonly used

Definitive treatment (endocrinology to guide):

• Antithyroid drugs (methimazole, PTU)
• Radioactive iodine ablation
• Thyroidectomy

PCP role:

1. Recognize hyperthyroidism
2. Confirm with labs (TSH, free T4)
3. Start beta-blocker for symptom control
4. Refer to endocrinology for definitive management
5. Monitor for complications (atrial fibrillation, osteoporosis)

Do NOT start antithyroid drugs without endocrinology guidance unless:

• Endocrinology unavailable and patient significantly symptomatic
• Clear Graves’ disease with no contraindications
• If starting: methimazole preferred; check CBC and LFTs first

Management by diagnosis#

Graves’ disease#

Education:

• Autoimmune condition; antibodies stimulate thyroid
• Three treatment options: medication, radioactive iodine, surgery
• Eye disease can occur/worsen independent of thyroid treatment
• Lifelong monitoring needed even after treatment

Treatment (endocrinology to initiate definitive therapy):

Symptom control (PCP can start):

Beta-blocker considerations:

• Elderly: Start at lower doses (propranolol 10 mg TID, atenolol 25 mg daily); monitor for bradycardia, hypotension
• Pregnancy: Propranolol and metoprolol acceptable; monitor for fetal bradycardia and IUGR with prolonged use
• Asthma: Use cardioselective beta-blocker (atenolol, metoprolol) at lowest effective dose; avoid propranolol
• Diabetes: May mask hypoglycemia symptoms; use with caution

Antithyroid drugs (endocrinology to initiate):

Agranulocytosis warning: Rare (<0.5%) but serious. Instruct patient: if fever, sore throat, mouth sores → stop medication and get CBC immediately.

Follow-up: Endocrinology manages definitive treatment. PCP role: monitor for complications, manage comorbidities, ensure follow-up.

Hyperthyroidism in pregnancy#

Key points:

• Untreated hyperthyroidism increases risk of preeclampsia, preterm birth, low birth weight
• PTU preferred in first trimester (methimazole teratogenic—aplasia cutis, choanal atresia)
• Methimazole preferred in 2nd/3rd trimester (PTU hepatotoxicity risk)
• Target free T4 at upper limit of normal (mild hyperthyroidism better tolerated than hypothyroidism)
• TSI crosses placenta—can cause fetal/neonatal hyperthyroidism

PCP role: Recognize and refer urgently to endocrinology and MFM. Do not delay treatment.

Toxic multinodular goiter / Toxic adenoma#

Education:

• Autonomous thyroid tissue producing excess hormone
• Does not respond to antithyroid drugs long-term (will recur)
• Definitive treatment: radioactive iodine or surgery

Treatment:

• Beta-blocker for symptom control
• Refer to endocrinology for RAIU scan and definitive treatment planning
• Antithyroid drugs may be used short-term to achieve euthyroid state before RAI or surgery

Follow-up: Endocrinology to manage.

Subacute thyroiditis (de Quervain’s)#

Education:

• Usually follows viral illness
• Self-limited (weeks to months)
• Triphasic course: hyperthyroid → hypothyroid → euthyroid
• Most recover normal thyroid function

Treatment:

Antithyroid drugs NOT indicated—thyroid is releasing preformed hormone, not making new hormone.

Follow-up: TSH every 4-6 weeks until normalized. ~15% develop permanent hypothyroidism.

Postpartum thyroiditis#

Education:

• Autoimmune thyroiditis occurring 2-12 months postpartum
• Biphasic: hyperthyroid (2-6 months) → hypothyroid (4-8 months) → recovery
• ~20-30% develop permanent hypothyroidism
• Higher risk with positive TPO antibodies, type 1 diabetes, prior postpartum thyroiditis

Treatment:

• Hyperthyroid phase: beta-blocker if symptomatic (safe in breastfeeding)
• Hypothyroid phase: levothyroxine if symptomatic or TSH >10
• Antithyroid drugs NOT indicated

Follow-up: TSH every 4-6 weeks during symptomatic phases; annually thereafter (risk of permanent hypothyroidism).

Subclinical hyperthyroidism#

Definition: Low TSH (<0.4) with normal free T4 and T3

Risk stratification:

• TSH 0.1-0.4: lower risk; often observe
• TSH <0.1: higher risk of atrial fibrillation, osteoporosis

Who to treat:

• TSH <0.1 persistently (after repeat testing)
• Age >65 (higher AF risk)
• Cardiac disease or risk factors
• Osteoporosis or fracture risk
• Symptomatic

Who to observe:

• TSH 0.1-0.4 with no symptoms or risk factors
• Younger patients without cardiac disease

Treatment: Refer to endocrinology if treatment indicated.

Follow-up: Repeat TSH in 6-8 weeks; if persistent, every 6-12 months if observing.

Follow-up#

Initial evaluation:

• 2-4 weeks after starting beta-blocker to assess symptom control
• Sooner if severe symptoms or concern for complications

After endocrinology referral:

• PCP continues to monitor for complications
• Ensure patient attending endocrinology appointments
• Monitor for atrial fibrillation, osteoporosis, cardiovascular disease

Long-term monitoring (post-treatment):

• After RAI or surgery: will need lifelong levothyroxine; TSH every 6-8 weeks until stable, then annually
• After antithyroid drugs: monitor for relapse (30-50% relapse rate after stopping)

Return precautions:

• Fever, sore throat, mouth sores (agranulocytosis if on antithyroid drugs)
• Worsening palpitations or new irregular heartbeat
• Chest pain or shortness of breath
• Eye pain, vision changes, or worsening eye symptoms
• Confusion, high fever, severe agitation (thyroid storm)

Patient instructions#

• Your thyroid gland is overactive and making too much thyroid hormone. This speeds up your body’s metabolism.
• The medication we’re starting (beta-blocker) will help control your symptoms like fast heartbeat and shakiness. It does not fix the underlying problem.
• You will need to see an endocrinologist (thyroid specialist) for treatment of the underlying cause.
• Avoid caffeine and other stimulants, which can worsen symptoms.
• If you’re on methimazole or PTU: call us immediately if you develop fever, sore throat, or mouth sores—stop the medication and get a blood test right away.
• Watch for signs of thyroid storm (emergency): high fever, very fast heartbeat, confusion, severe agitation. Call 911 if this happens.
• If you have eye symptoms (bulging, double vision, pain), let us know—you may need to see an eye specialist.
• Do not take biotin supplements (including many multivitamins) for 2-3 days before thyroid blood tests, as they can interfere with results.

Smartphrase snippets#

.HYPERTHYROIDNEW Patient presents with symptoms concerning for hyperthyroidism including [palpitations/weight loss/tremor/heat intolerance]. TSH [value] (low), free T4 [value] (elevated). Exam notable for [tachycardia/tremor/goiter/eye findings]. Started propranolol [dose] for symptom control. Referred to endocrinology for further evaluation and definitive management. Patient counseled on return precautions including signs of thyroid storm and atrial fibrillation.

.HYPERTHYROIDFOLLOWUP Hyperthyroidism follow-up. Currently on [beta-blocker/antithyroid drug]. Symptoms [improved/stable/worsened]. HR [value], weight [value]. Labs: TSH [value], free T4 [value]. [If on antithyroid drug: No symptoms of agranulocytosis; CBC reviewed.] Plan: [continue current regimen/adjust dose/continue endocrinology follow-up]. Return precautions reviewed.

.SUBCLINICALHYPER Incidental finding of low TSH [value] with normal free T4 [value] consistent with subclinical hyperthyroidism. Patient is [asymptomatic/mildly symptomatic]. Risk factors for complications: [age >65/cardiac disease/osteoporosis/none]. Plan: Repeat TSH in 6-8 weeks to confirm persistence. If persistent, will [refer to endocrinology/continue monitoring based on risk stratification]. Patient advised to report palpitations, weight loss, or other hyperthyroid symptoms.

Related pages#

• Palpitations — hyperthyroidism as cause
• Weight loss — hyperthyroidism as cause
• Anxiety — can mimic or coexist with hyperthyroidism
• Hypothyroid — opposite presentation; may develop after treatment
• Atrial fibrillation (problem) — hyperthyroidism-induced AF
• Osteoporosis (problem) — long-term hyperthyroidism increases fracture risk

Coding/billing notes#

• E05.00: Thyrotoxicosis with diffuse goiter without thyrotoxic crisis (Graves')
• E05.10: Thyrotoxicosis with toxic single thyroid nodule without thyrotoxic crisis
• E05.20: Thyrotoxicosis with toxic multinodular goiter without thyrotoxic crisis
• E05.90: Thyrotoxicosis, unspecified without thyrotoxic crisis
• E06.1: Subacute thyroiditis
• O90.5: Postpartum thyroiditis