This chapter will review the pharmacotherapy for management of myasthenia crisis, Guillain-Barre syndrome, and antithrombotic-induced intracranial hemorrhage according to expert opinion.
Myasthenia crisis
Definitions
Myasthenia gravis (MG)
Autoimmune disease targeting acetylcholine receptors on the postsynaptic side of neuromuscular junctions.
Myasthenia crisis
Worsening of MG with respiratory failure.
Precipitating factors
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Respiratory infection
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Emotional stress
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Physiological stress (e.g., trauma, surgery)
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Tapering of immunosuppressants
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Drugs: aminoglycosides, fluoroquinolones, macrolides, tetracyclines, neuromuscular blocking agents, magnesium, β-blockers, verapamil, procainamide, quinidine
Management ( table 14.1 )
DRUG | STANDARD DOSING | ONSET OF BENEFIT | TIME TO PEAK BENEFIT | COMMENTS |
---|---|---|---|---|
Rapid Immunotherapies | ||||
Plasma exchange | — | 1–7 days | 1–3 weeks | Directly removes acetylcholine receptor antibodies More effective and works faster than IVIG (2016 international consensus statement by the Myasthenia Gravis Foundation of America) |
Intravenous immunoglobulin (IVIG) | 0.4 g/kg IV daily × 5 days or 1 g/kg IV daily ×1–2 days | 1–2 weeks | 1–3 weeks | Clinical trials show equivalence to plasma exchange |
Symptomatic Therapy | ||||
Pyridostigmine | PO: 60–120 mg q6h IV/IM: 2–4 mg q6h (off-label) | 10–15 min | 2 h |
|
Chronic Immunotherapies (PO) | ||||
Prednisone | Initial: 20 mg daily Target: 1 mg/kg/day Max: 100 mg/day | 2–3 weeks | 5–6 months |
|
Azathioprine | 1–3 mg/kg/day | 6–12 months | 1–2 yr |
|
Mycophenolate | 0.5–1.5 g BID | 6–12 months | 1–2 yr |
|
Cyclosporine | 2.5 mg/kg BID | ∼6 months | ∼12 months |
|
Tacrolimus | 3–5 mg daily | |||
Surgery | ||||
Thymectomy | — | 1–10 yr | 1–10 yr |