Myasthenia Gravis - Exacerbation/Crisis¶

VERSION: 1.1 CREATED: January 24, 2026 REVISED: January 24, 2026 STATUS: Draft - Pending Review

DIAGNOSIS: Myasthenia Gravis - Exacerbation/Crisis

ICD-10: G70.00 (Myasthenia gravis without exacerbation), G70.01 (Myasthenia gravis with exacerbation), G70.1 (Toxic myoneural disorders)

SCOPE: Evaluation and management of acute myasthenic exacerbation and myasthenic crisis in adults. Covers respiratory monitoring, immunotherapy (IVIg and plasmapheresis), medications to avoid, and ICU management. Excludes new diagnosis workup, chronic maintenance therapy, Lambert-Eaton myasthenic syndrome (LEMS), and congenital myasthenic syndromes.

CLINICAL SYNONYMS: MG crisis, myasthenic crisis, MG exacerbation, acute MG flare, myasthenia gravis flare

KEY DEFINITIONS: - MG Exacerbation: Worsening weakness requiring medication adjustment or immunotherapy but NOT requiring intubation - Myasthenic Crisis: Respiratory failure requiring mechanical ventilation OR FVC <15-20 mL/kg - Cholinergic Crisis: Excess acetylcholinesterase inhibitors causing weakness with muscarinic symptoms (SLUDGE: Salivation, Lacrimation, Urination, Defecation, GI distress, Emesis)

KEY CLINICAL FEATURES: - Fatigable weakness (worsens with activity, improves with rest) - Ptosis and diplopia (ocular MG or generalized with ocular involvement) - Bulbar weakness: dysarthria, dysphagia, facial weakness - Limb weakness (proximal > distal, arms > legs) - Respiratory weakness: dyspnea, orthopnea, weak cough - Crisis triggers: Infection, surgery, medication changes, pregnancy, stress

PRIORITY KEY: STAT = Immediate | URGENT = Within hours | ROUTINE = Standard | EXT = Extended/atypical cases | - = Not applicable to this setting

⚡ RESPIRATORY FAILURE WARNING

15-20% of MG exacerbations progress to crisis. Monitor FVC and NIF every 4-6 hours. Intubate if FVC <15 mL/kg or NIF weaker than -20 cmH2O.

⚠️ MEDICATION SAFETY

Many common medications worsen MG. See Medications to AVOID section before prescribing.

═══════════════════════════════════════════════════════════════ SECTION A: ACTION ITEMS ═══════════════════════════════════════════════════════════════

1. LABORATORY WORKUP¶

1A. Essential/Core Labs¶

Test	Rationale	Target Finding	ED	HOSP	OPD	ICU
CBC with differential	Infection as trigger, baseline	Normal or elevated WBC if infected	STAT	STAT	—	STAT
CMP (BMP + LFTs)	Electrolytes, renal/hepatic function	Normal; hypokalemia worsens weakness	STAT	STAT	—	STAT
Magnesium	Hypomagnesemia worsens NMJ transmission	>1.8 mg/dL	STAT	STAT	—	STAT
Phosphorus	Hypophosphatemia causes weakness	>2.5 mg/dL	STAT	STAT	—	STAT
TSH	Thyroid disease common comorbidity	Normal	URGENT	ROUTINE	—	URGENT
Blood glucose	Hyperglycemia worsens outcomes	<180 mg/dL	STAT	STAT	—	STAT
Urinalysis	UTI as trigger	Negative for infection	STAT	ROUTINE	—	STAT
Blood cultures	If febrile or sepsis suspected	Negative	STAT	STAT	—	STAT
Procalcitonin	Differentiate infection vs non-infectious flare	<0.5 ng/mL if non-infectious	URGENT	ROUTINE	—	URGENT
ABG or VBG	Respiratory status, CO2 retention	PaCO2 <45 mmHg, pH >7.35	STAT	STAT	—	STAT

1B. Extended Workup (Second-line)¶

Test	Rationale	Target Finding	ED	HOSP	OPD	ICU
AChR (acetylcholine receptor) antibody	Confirm diagnosis if unknown	Document if positive (~85% of generalized MG)	—	ROUTINE	—	ROUTINE
MuSK antibody	If AChR negative	Document if positive (~40% of AChR-negative)	—	ROUTINE	—	ROUTINE
LRP4 antibody	If AChR and MuSK negative	Document if positive	—	EXT	—	EXT
Anti-striated muscle antibody	Thymoma association	If positive, CT chest	—	ROUTINE	—	ROUTINE
Hepatitis B surface antigen	Pre-IVIg screening	Negative	—	URGENT	—	URGENT
Quantitative immunoglobulins	IgA deficiency (IVIg contraindication)	IgA >7 mg/dL	—	URGENT	—	URGENT
PT/INR, PTT	Pre-PLEX	Normal	—	URGENT	—	STAT
Type and screen	Pre-PLEX	Available	—	URGENT	—	STAT
Fibrinogen	Pre-PLEX baseline	Normal	—	URGENT	—	STAT
Troponin	Cardiac involvement, stress	Normal	URGENT	ROUTINE	—	STAT
BNP/NT-proBNP	Heart failure assessment	Normal	URGENT	ROUTINE	—	STAT

1C. Rare/Specialized (Refractory or Atypical)¶

Test	Rationale	Target Finding	ED	HOSP	OPD	ICU
Cortisol (random or AM)	Adrenal insufficiency if on chronic steroids	Normal stress response	—	ROUTINE	—	ROUTINE
Acetylcholinesterase inhibitor level	Cholinergic crisis concern (if available)	Therapeutic range	—	EXT	—	EXT
Paraneoplastic panel	Occult malignancy	Negative	—	EXT	—	EXT
Respiratory viral panel	Viral trigger	Document if positive	—	ROUTINE	—	ROUTINE

2. DIAGNOSTIC IMAGING & STUDIES¶

2A. Essential/First-line¶

Study	Timing	Target Finding	Contraindications	ED	HOSP	OPD	ICU
Chest X-ray	On admission	Aspiration, atelectasis, pneumonia	None	STAT	STAT	—	STAT
ECG	On admission	Arrhythmia, QT prolongation	None	STAT	STAT	—	STAT
Forced vital capacity (FVC)	Serial q4-6h (q2h if declining)	FVC >15-20 mL/kg	Facial weakness limiting seal	STAT	STAT	—	STAT
Negative inspiratory force (NIF)	Serial q4-6h (q2h if declining)	NIF more negative than -20 cmH2O	Facial weakness	STAT	STAT	—	STAT

2B. Extended¶

Study	Timing	Target Finding	Contraindications	ED	HOSP	OPD	ICU
CT chest with contrast	If thymoma not previously evaluated	Thymoma or thymic hyperplasia	Contrast allergy, renal impairment	—	ROUTINE	—	ROUTINE
CT chest without contrast	Thymoma evaluation (if contrast contraindicated)	Thymic abnormality	None	—	ROUTINE	—	ROUTINE
Swallow evaluation	Bulbar symptoms	Aspiration risk	None	—	URGENT	—	URGENT
Repetitive nerve stimulation	If diagnosis uncertain	Decremental response >10%	None	—	ROUTINE	—	ROUTINE
Single-fiber EMG	If RNS negative but MG suspected	Increased jitter, blocking	None	—	EXT	—	EXT

2C. Rare/Specialized¶

Study	Timing	Target Finding	Contraindications	ED	HOSP	OPD	ICU
PET-CT	Occult thymoma or malignancy	Tumor identification	Hemodynamic instability	—	EXT	—	EXT
Ice pack test	Bedside diagnostic (ptosis)	Improvement with cooling	None	STAT	STAT	—	STAT

3. TREATMENT¶

CRITICAL: Myasthenic crisis is a medical emergency. Secure airway early if deteriorating. Do NOT delay intubation.

Crisis vs Cholinergic Crisis Differentiation¶

Feature	Myasthenic Crisis	Cholinergic Crisis
Pupils	Normal or mydriasis	Miosis
Secretions	Normal or dry	Excessive (SLUDGE)
Fasciculations	Absent	Present
Heart rate	Normal or tachy	Bradycardia
Response to edrophonium	Improvement	Worsening
Management	IVIg/PLEX, stop AChEI temporarily	Stop AChEI, supportive care

3A. Acute/Emergent - Airway and Respiratory Support¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Supplemental oxygen	INH	Hypoxemia	2-6 L/min NC; 15 L/min NRB :: INH :: PRN :: Titrate to O2 sat >94%; escalate as needed	None	O2 sat, RR	STAT	STAT	—	STAT
Endotracheal intubation	—	Respiratory failure	N/A :: — :: :: Intubate if FVC <15 mL/kg, NIF >-20 cmH2O, or clinical deterioration; AVOID succinylcholine (may have prolonged block); use rocuronium (may need higher dose)	—	ETT position, ventilator settings	STAT	STAT	—	STAT
Non-invasive ventilation (BiPAP)	—	Bridge to intubation or mild hypoventilation	IPAP 10-15; EPAP 5 :: — :: continuous :: BiPAP may temporize; NOT a substitute for intubation in true crisis	Severe respiratory failure, inability to protect airway	RR, TV, O2 sat, CO2	STAT	STAT	—	STAT
Mechanical ventilation	—	Respiratory failure	N/A :: — :: :: Lung-protective ventilation; expect prolonged wean; daily SBT when improved	—	ABG, ventilator parameters	—	—	—	STAT

3B. Immunotherapy - First-line for Crisis/Severe Exacerbation¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
IVIg (immune globulin IV)	IV	Myasthenic crisis or severe exacerbation	0.4 g/kg/day x 5 days; 1 g/kg/day x 2 days :: IV :: daily x 5 days :: 0.4 g/kg/day IV for 5 days (preferred) OR 1 g/kg/day x 2 days; infuse slowly day 1	IgA deficiency with anti-IgA antibodies; severe renal impairment; recent MI/stroke (thrombosis risk)	Renal function daily, headache, infusion reactions; pre-medicate	—	STAT	—	STAT
Plasmapheresis (PLEX)	—	Myasthenic crisis or severe exacerbation	5 exchanges over 7-14 days :: — :: QOD x 5 :: 5 exchanges (1-1.5 plasma volumes per exchange) over 7-14 days; typically QOD	Hemodynamic instability, severe sepsis, poor IV access	BP, electrolytes, coagulation, fibrinogen	—	STAT	—	STAT

IVIg vs PLEX Selection: - IVIg preferred: Hemodynamic instability, autonomic dysfunction, difficult vascular access, outpatient - PLEX preferred: Severe/rapidly worsening crisis (faster onset), IgA deficiency, MuSK-positive MG (may respond better), preparation for thymectomy - Efficacy: Both effective; PLEX may work faster (days) vs IVIg (5-7 days) - Duration: Effects last 3-6 weeks; bridge to chronic immunotherapy

3C. Cholinesterase Inhibitors¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Pyridostigmine	PO	Symptomatic treatment	30 mg TID; 60 mg TID; 60 mg QID; 90 mg QID :: PO :: TID-QID :: Start 30-60 mg TID; titrate by 30 mg/dose q2-3d; max ~120 mg q4h; usual maintenance 60-90 mg q4-6h	Mechanical bowel/bladder obstruction	Cholinergic symptoms (SLUDGE), HR	—	ROUTINE	—	ROUTINE
Pyridostigmine (in crisis)	—	During crisis	HOLD or reduce :: — :: :: HOLD pyridostigmine in intubated patients or suspected cholinergic crisis; restart at low dose when improving	Cholinergic crisis	Secretions, HR	—	STAT	—	STAT
Neostigmine	IV/IM	If NPO and needs AChEI	0.5 mg IV q3h; 1.5 mg IM q3h :: IV/IM :: q3h :: 0.5 mg IV or 1.5 mg IM roughly equivalent to 60 mg PO pyridostigmine; use ONLY if cannot take PO and essential	Cholinergic toxicity	HR, secretions	—	URGENT	—	URGENT
Glycopyrrolate	PO/IV	Cholinergic side effects	1 mg PO TID; 0.2 mg IV PRN :: PO/IV :: TID :: 1-2 mg PO TID for secretions/GI effects; 0.2 mg IV PRN; does not cross BBB	Glaucoma, severe cardiac disease	HR, urinary retention	—	ROUTINE	—	ROUTINE

3D. Corticosteroids (Use with CAUTION)¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Prednisone (high-dose, post-crisis)	PO	Crisis treated with IVIg/PLEX, improving	60 mg daily; 1 mg/kg daily :: PO :: daily :: Start 60 mg (or 1 mg/kg) daily AFTER day 3 of IVIg/PLEX if improving; for patients whose crisis is being treated; taper once stable	Active infection (relative)	Glucose, BP, K+; already covered by IVIg/PLEX	—	STAT	—	STAT
Prednisone (low-dose start)	PO	Stable patient, outpatient, new start	10 mg daily; 20 mg daily :: PO :: daily :: Start LOW (10-20 mg daily) and increase slowly by 10 mg q5-7d to target 1 mg/kg/day; for OUTPATIENT or STABLE inpatients not in crisis; HIGH-DOSE INITIATION CAN WORSEN MG	Active infection (relative), brittle MG without IVIg/PLEX cover	Glucose, BP, K+; WATCH FOR TRANSIENT WORSENING days 5-10	—	ROUTINE	ROUTINE	—
Methylprednisolone	IV	Severe exacerbation (with IVIg/PLEX cover)	500 mg daily x 3-5 days; 1000 mg daily x 3-5 days :: IV :: daily x 3-5 days :: 500-1000 mg IV daily x 3-5 days; ONLY with IVIg/PLEX coverage due to risk of transient worsening	Active untreated infection	Glucose, BP, K+, psychiatric effects	—	URGENT	—	URGENT

⚠️ STEROID WARNING: High-dose corticosteroids can cause transient worsening of MG (typically days 5-10). Two approaches: - Crisis/Post-treatment: If improving with IVIg/PLEX after day 3, can start prednisone 60 mg (or 1 mg/kg) since already covered - Outpatient/Stable: Start LOW (10-20 mg) and titrate slowly to avoid worsening in patients not covered by IVIg/PLEX

3E. Medications to AVOID¶

CRITICAL: The following medications can worsen myasthenia gravis and should be avoided or used with extreme caution:

Category	Medications to AVOID	Alternative
Antibiotics	Aminoglycosides (gentamicin, tobramycin, amikacin), fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin), macrolides (azithromycin, erythromycin), telithromycin	Penicillins, cephalosporins, carbapenems generally safer
Cardiac	Beta-blockers (all), calcium channel blockers (verapamil, diltiazem), procainamide, quinidine, lidocaine	Use with caution; cardiology consult
Neuromuscular blockers	Succinylcholine (prolonged block), non-depolarizing agents (prolonged)	If needed, use reduced dose rocuronium with sugammadex available
Psychiatric	Lithium, phenothiazines, benzodiazepines (high dose)	SSRIs generally safe
Anticonvulsants	Phenytoin, gabapentin (rare reports)	Levetiracetam, valproate safer
Other	Magnesium IV (high dose), D-penicillamine, botulinum toxin, quinine, chloroquine, iodinated contrast (caution)	Avoid if possible

3F. Supportive Care¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Enoxaparin	SC	DVT prophylaxis	40 mg daily; 30 mg BID :: SC :: daily :: 40 mg SC daily; 30 mg BID if BMI >40; hold if CrCl <30; HOLD if LP planned within 12 hours	Active bleeding, HIT, pending LP	Platelet count, bleeding	—	STAT	—	STAT
Heparin (UFH)	SC	DVT prophylaxis (renal impairment)	5000 units q8h; 5000 units q12h :: SC :: q8-12h :: 5000 units SC q8-12h if CrCl <30; HOLD if LP planned within 4-6 hours	Active bleeding, HIT, pending LP	Platelet count	—	STAT	—	STAT
Famotidine	IV/PO	Stress ulcer prophylaxis (if on steroids)	20 mg BID; 40 mg daily :: IV/PO :: BID :: 20 mg IV/PO BID or 40 mg daily	None significant	None	—	ROUTINE	—	ROUTINE
Insulin (regular)	IV/SC	Steroid-induced hyperglycemia	Sliding scale; basal-bolus :: IV/SC :: per protocol :: Sliding scale or basal-bolus; target glucose <180 mg/dL	Hypoglycemia	Glucose q4-6h	—	ROUTINE	—	STAT
Acetaminophen	PO/IV	Fever, mild pain	650 mg q6h; 1000 mg q6h :: PO/IV :: q6h :: 650-1000 mg q6h; max 4 g/day	Severe hepatic impairment	LFTs if prolonged	STAT	STAT	—	STAT
SCDs (sequential compression devices)	—	DVT prophylaxis	N/A :: — :: continuous :: Bilateral lower extremity SCDs	DVT in that extremity	Skin integrity	STAT	STAT	—	STAT

3G. Long-term Immunosuppression (Initiate/Continue as Indicated)¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Azathioprine	PO	Steroid-sparing agent	50 mg daily; 100 mg daily; 150 mg daily :: PO :: daily :: Start 50 mg daily; increase by 50 mg q2-4wk to 2-3 mg/kg/day; check TPMT before starting	TPMT deficiency, pregnancy	CBC weekly x 4, then monthly; LFTs monthly	—	ROUTINE	—	—
Mycophenolate mofetil	PO	Steroid-sparing agent	500 mg BID; 1000 mg BID; 1500 mg BID :: PO :: BID :: Start 500 mg BID; increase to 1000-1500 mg BID over 2-4 weeks	Pregnancy, hypersensitivity	CBC q2wk x 2mo, then monthly; LFTs	—	ROUTINE	—	—
Rituximab	IV	Refractory MG, MuSK-positive MG	375 mg/m² weekly x 4 weeks; 1000 mg q2wk x 2 :: IV :: weekly x 4 or q2wk x 2 :: 375 mg/m² weekly x 4 OR 1000 mg x 2 doses (2 weeks apart); pre-medicate with methylpred, acetaminophen, diphenhydramine	Active infection, HBV (screen first)	Infusion reactions, CD19/CD20, immunoglobulins	—	EXT	—	EXT

4. OTHER RECOMMENDATIONS¶

4A. Referrals & Consults¶

Recommendation	ED	HOSP	OPD	ICU
Neurology consult for crisis management, immunotherapy guidance, and medication safety review	STAT	STAT	—	STAT
Pulmonology consult for respiratory function monitoring and ventilator wean planning if intubated	URGENT	URGENT	—	STAT
Critical care consult for ICU admission given FVC <20 mL/kg or impending respiratory failure	URGENT	STAT	—	STAT
Thoracic surgery consult for thymectomy planning if thymoma identified or considering elective thymectomy	—	ROUTINE	—	ROUTINE
Speech therapy for swallow evaluation and aspiration risk assessment given bulbar symptoms	—	URGENT	—	URGENT
Physical therapy for mobility assessment and safe transfer training given fluctuating weakness	—	URGENT	—	URGENT
Occupational therapy for ADL assessment and energy conservation strategies to manage fatigue	—	ROUTINE	—	ROUTINE
Respiratory therapy for airway clearance and pulmonary toilet given weak cough and secretion management	STAT	STAT	—	STAT
Pharmacy consult to review all medications for MG-exacerbating drugs (see medications to avoid list)	—	URGENT	—	URGENT
Social work for discharge planning and Myasthenia Gravis Foundation support resources	—	ROUTINE	—	ROUTINE

4B. Patient Instructions¶

Recommendation	ED	HOSP	OPD
Return immediately if worsening weakness or breathing difficulty develops (may indicate crisis requiring intubation)	STAT	—	STAT
Do not skip or suddenly stop immunosuppressive medications as this may trigger severe exacerbation	STAT	STAT	STAT
Carry MG medical alert card listing medications to avoid (aminoglycosides, fluoroquinolones, beta-blockers, etc.)	—	STAT	STAT
Take pyridostigmine 30-60 minutes before meals to improve swallowing and reduce aspiration risk	—	ROUTINE	ROUTINE
Report fever or signs of infection promptly as infection is a common exacerbation trigger	STAT	STAT	STAT
Avoid extreme heat as high temperatures worsen neuromuscular transmission and increase weakness	—	ROUTINE	ROUTINE
Get adequate rest and avoid overexertion; fatigue worsens throughout the day in MG	—	ROUTINE	ROUTINE
Do not drive if diplopia or ptosis impairs vision; symptoms may fluctuate unpredictably	STAT	STAT	STAT
Contact Myasthenia Gravis Foundation (www.myasthenia.org) for patient support and educational resources	—	ROUTINE	ROUTINE

4C. Lifestyle & Prevention¶

Recommendation	ED	HOSP	OPD
Aspiration precautions including thickened liquids and upright positioning given bulbar weakness	STAT	STAT	—
Fall precautions including walker and bed rails due to fluctuating proximal weakness	STAT	STAT	STAT
Medication reconciliation before any new prescription to avoid MG-exacerbating drugs	STAT	STAT	STAT
Avoid live vaccines while on immunosuppression; flu and pneumococcal vaccines recommended to prevent infections	—	ROUTINE	ROUTINE
Stress management techniques as psychological stress can trigger MG exacerbations	—	ROUTINE	ROUTINE
Maintain good sleep hygiene as fatigue and sleep deprivation worsen MG symptoms	—	ROUTINE	ROUTINE
Use energy conservation techniques including pacing activities and scheduling rest periods	—	ROUTINE	ROUTINE

═══════════════════════════════════════════════════════════════ SECTION B: REFERENCE (Expand as Needed) ═══════════════════════════════════════════════════════════════

5. DIFFERENTIAL DIAGNOSIS¶

Alternative Diagnosis	Key Distinguishing Features	Tests to Differentiate
Guillain-Barré syndrome	Ascending weakness, areflexia, no fluctuation	CSF (albuminocytologic dissociation), EMG/NCS
Lambert-Eaton syndrome	Proximal weakness, autonomic symptoms, reflexes improve with exercise	VGCC antibodies, EMG (incremental response)
Botulism	Descending weakness, pupil involvement, GI symptoms	Stool/serum toxin, EMG
Brainstem stroke	Acute onset, crossed findings, other cranial nerve signs	MRI brain
Multiple sclerosis	CNS symptoms, sensory involvement, different time course	MRI brain/spine, CSF
Thyroid eye disease	Thyroid dysfunction, proptosis, restrictive ophthalmopathy	TFTs, orbital imaging
Oculopharyngeal muscular dystrophy	Older onset, slowly progressive, no fluctuation	Genetic testing, muscle biopsy
Mitochondrial myopathy	Progressive, elevated lactate, other organ involvement	Lactate, muscle biopsy, genetic testing
Drug-induced MG	Recent D-penicillamine, checkpoint inhibitors	Medication history, antibodies
Cholinergic crisis	SLUDGE symptoms, miosis, bradycardia	Clinical, response to stopping AChEI

6. MONITORING PARAMETERS¶

Parameter	Frequency	Target/Threshold	Action if Abnormal	ED	HOSP	OPD	ICU
Forced vital capacity (FVC)	q4-6h; q2h if declining	>15-20 mL/kg	Intubate if <15 mL/kg	STAT	STAT	—	STAT
Negative inspiratory force (NIF)	q4-6h; q2h if declining	More negative than -20 cmH2O	Intubate if weaker than -20 cmH2O	STAT	STAT	—	STAT
Oxygen saturation	Continuous	>94%	Supplement O2, consider intubation	STAT	STAT	—	STAT
Neurological exam (strength)	q4-8h	Stable or improving	Escalate therapy if worsening	STAT	STAT	ROUTINE	STAT
Swallow function	Daily if bulbar symptoms	Safe swallow	NPO, NG tube if unsafe	—	STAT	—	STAT
Blood glucose	q6h if on steroids	<180 mg/dL	Insulin adjustment	—	ROUTINE	—	STAT
Renal function	Daily during IVIg	Cr stable	Hold IVIg, hydrate if rising	—	STAT	—	STAT
Electrolytes (K+, Mg)	Daily	K+ >3.5, Mg >1.8	Replete aggressively	STAT	STAT	—	STAT
Heart rate/rhythm	Continuous	Sinus rhythm, HR 60-100	Evaluate for autonomic dysfunction	STAT	STAT	—	STAT
Blood pressure	q4h	SBP 100-160	Evaluate for autonomic dysfunction	STAT	STAT	—	STAT
Cholinergic symptoms	Each dose of pyridostigmine	Absent	Reduce dose, consider cholinergic crisis	—	ROUTINE	—	ROUTINE

7. DISPOSITION CRITERIA¶

Disposition	Criteria
ICU admission	FVC <20 mL/kg or declining; NIF weaker than -30 cmH2O; rapid progression; bulbar dysfunction with aspiration risk; need for intubation/BiPAP
Step-down/telemetry	Stable FVC >20 mL/kg; improving or stable exam; receiving IVIg/PLEX; no bulbar symptoms
General floor	Mild exacerbation; FVC >30 mL/kg and stable; no bulbar symptoms; stable on oral medications
Discharge home	Stable or improved x 24-48 hours; FVC stable >30 mL/kg; adequate oral intake; medications optimized; outpatient follow-up arranged
Acute rehabilitation	Significant residual weakness after crisis; requires intensive therapy; medically stable

8. EVIDENCE & REFERENCES¶

Recommendation	Evidence Level	Source
IVIg and PLEX equally effective for MG exacerbation	Class I, Level A	Gajdos et al. Cochrane 2012
IVIg 2 g/kg total dose standard	Class I, Level A	Zinman et al. Lancet Neurol 2007
PLEX effective for MG crisis	Class I, Level A	Gajdos et al. Cochrane 2012
FVC and NIF for respiratory monitoring	Class II, Level B	Rabinstein & Wijdicks. Neurology 2003
Pyridostigmine for symptomatic treatment	Class I, Level A	Mehndiratta et al. Cochrane 2014
Corticosteroids can cause initial worsening	Class II, Level B	Palace et al. Lancet Neurol 2012
Azathioprine as steroid-sparing agent	Class I, Level B	Palace et al. NEJM 1998
Rituximab effective in refractory/MuSK+ MG	Class II, Level C	Nowak et al. Neurology 2022
Medications to avoid in MG	Class III, Level C	Juel. Semin Neurol 2004
Thymectomy beneficial in generalized MG	Class I, Level B	Wolfe et al. NEJM 2016 (MGTX Trial)

CHANGE LOG¶

v1.1 (January 24, 2026) - Citation verification: Corrected Gajdos Cochrane PMID (23235588), MGTX trial PMID (27509100)

v1.0 (January 24, 2026) - Initial template creation - Includes respiratory monitoring protocol - IVIg and PLEX protocols for crisis - Comprehensive medications to avoid list - Cholinergic vs myasthenic crisis differentiation - Steroid initiation guidance with worsening warning

APPENDIX A: Myasthenia Gravis Foundation of America (MGFA) Clinical Classification¶

Class	Description
I	Ocular weakness only (ptosis, diplopia)
II	Mild generalized weakness ± ocular
IIa	Predominantly limb/axial
IIb	Predominantly oropharyngeal/respiratory
III	Moderate generalized weakness ± ocular
IIIa	Predominantly limb/axial
IIIb	Predominantly oropharyngeal/respiratory
IV	Severe generalized weakness ± ocular
IVa	Predominantly limb/axial
IVb	Predominantly oropharyngeal/respiratory
V	Intubation required (with or without mechanical ventilation)

Clinical Use: Document at admission and track progression. Class IIb, IIIb, IVb (bulbar predominant) and any Class IV/V require ICU monitoring.

APPENDIX B: Quantitative Myasthenia Gravis (QMG) Score¶

Standardized 13-item scoring system for disease severity. Each item scored 0-3 (total 0-39).

Item	Assessment
Diplopia	Lateral gaze duration
Ptosis	Upward gaze duration
Facial muscles	Eye closure strength
Swallowing	4 oz water
Speech	Counting to 50
Right arm extended	90° duration
Left arm extended	90° duration
FVC	% predicted
Right hand grip	Dynamometer
Left hand grip	Dynamometer
Head lift	Supine, 45° duration
Right leg extended	Supine, 45° duration
Left leg extended	Supine, 45° duration

Interpretation: - 0-9: Mild - 10-19: Moderate - ≥20: Severe

APPENDIX C: IVIg vs PLEX Quick Reference¶

Factor	IVIg	PLEX
Onset of action	5-7 days	2-3 days
Duration of effect	3-6 weeks	3-6 weeks
Administration	Peripheral IV possible	Central line usually required
Sessions	Daily x 5 days (or x2 days)	QOD x 5 (over ~2 weeks)
Hemodynamic tolerance	Better	Fluid shifts, hypotension risk
In pregnancy	Safe	Safe but challenging
Renal impairment	Caution (risk AKI)	Preferred
IgA deficiency	Contraindicated	Safe
MuSK+ MG	May be less effective	May be preferred
Before thymectomy	Either	Often preferred
Cost	Higher	Lower
Outpatient feasible	Yes	Difficult