Table 2.
Treatment options for MG
| Substances | Dose | Side effects | Contraindications and special remarks |
|---|---|---|---|
| Cholinesterase inhibitors | |||
| Pyridostigmin bromide (approved) | Single dose orally: 30–60 mg max. 360 mg/day | Stimulation of muscarinic AChR (smooth muscles, gland secretion): stomach crampi, nausea, vomiting, anorexia, diarrhea, urinary urgency, salivation/lacrivation, sweating, bronchial secretion, accommodation errors, miosis, bradycardia (rarely AV block), hypotonia stimulation of nicotinic AChR (skeletal muscles): muscle fasciculation, spasms, muscle weakness (depolarization block) | Absolute contraindications: asthma bronchiale, prostata hypertrophy, decompensated heart insufficiency, acute myocardial infarction, thyreotoxicosis relative contraindications: pregnancy, breast-feeding |
| Ambenonium chloride (off label) | Single dose orally 5–10 mg max. 40 mg/day | Fewer gastrointestinal side effects than pyridostigmin | Analog to pyridostigmin |
| Immunosuppressants | |||
| Glucocorticosteroids: prednisone prednisolone methylprednisolone (approved) | Oral therapy: 0.5–1.5 mg/kg Intravenous pulse therapy: 500–1000 mg/day for 1–3 days cave: initial transient deterioration especially of bulbar myasthenic symptoms—ICU monitoring and therapy necessary |
Gain of weight, cushingoid phenotype, acne, diabetes, susceptibility to infections and thrombosis, hypertonia, hypokaliema, edema, psychosis, osteoporosis with the risk of fractures, aseptic bone necrosis, cataract, glaucoma, psychological disorders (euphoria/depression), insomnia, steroid myopathy, gastric and duodenal ulcera | Severe infections, malignant diseases, severely reduced immune defense, pregnancy, breast-feeding severe infections, manifest gastric and duodenal ulcera, severe osteoporosis, psychiatric disorders, uncontrolled hypertonia, uncontrolled diabetes |
| Azathioprine (approved) | Induction dose: 2–3 mg/day/kg Maintenance dose: 1.5–2 mg/day/kg |
Susceptibility to infections, bone marrow depression (leukopenia, thrombopenia, rarely anemia), nausea, vomiting, diarrhea, fever, allergic reaction, hepatotoxicity, arthralgia, myalgia, alveolitis, pancreatitis, skin exanthema | Pregnancy: azathioprine may be prescribed in case of an appropriate indication. If a female patient is stable on azathioprine therapy should not be stopped Breast-feeding: azathioprine therapy does not exclude breast feeding No vaccinations with live vaccines! Success of vaccinations in general is uncertain Simultaneous admission of allopurinol or other xantinoxidase inhibitors leads to myelotoxicity and agranulocytosis—dose reduction to 25 % of azathioprine or switch from allopurinol to probenezid or benzbromaron severe bone marrow and liver and kidney damage |
| Ciclosporin A (off-label) | 2 (−5) mg/day/kg in two single doses | Hypertonia, nephrotoxicity (nephropathy, hyperkalemia), CNS-toxicity (tremor, paresthesia, seizures), posterior reversible encephalopathy syndrome, hepatotoxicity, hirsutism, gingiva hyperplasia, secondary malignancies, infections | Kidney failure, severe infections, malignant diseases, severely reduced immune defense, pregnancy, breast-feeding |
| Methotrexate (off-label) | 7.5–15 mg once per week max. 25 mg once per week in combination with folic acid (5 mg) 24 h after application | Hepatotoxicity, bow marrow depression, gastrointestinal symptoms, stomatitis, ulcera, exanthema, loss of hair, hyperuricemia, kidney failure, cystitis, lung fibrosis, cutaneous vasculitis, photosensitivity, psychiatric disorder, osteoporosis | Liver or kidney failure, severe infections, malignant diseases, severely reduced immune defense, pregnancy, breast-feeding, bone marrow depression, florid gastrointestinal ulcera |
| Mycophenolat mofetil (off-label) | 0.5–3 g/day in two single doses (mostly 2 × 1 g/day) | Gastrointestinal symptoms (nausea, vomiting, diarrhea, ulcera, gastrointestinal bleeding), bone marrow depression (leukopenia, anemia, thrombocytopenia), infections, risk for lymphoma under long-term therapy, progressive multifocal leukoencephalopathy (PML) | Severe infections, malignant diseases, severely reduced immune defense, pregnancy, breast-feeding |
| Tacrolimus (off-label) | 0.1–0.2 mg/day/kg in two single doses | Hypertonia, nephrotoxicity (nephropathy, hyperkalemia), ZNS-toxicity (tremor, paresthesia, seizures), posterior reversible encephalopathy syndrome, hepatotoxicity, hirsutism, gingivahyperplasia, secondary malignancies, infections | Kidney failure, severe infections, malignant diseases, severely reduced immune defense, pregnancy, breast-feeding |
| Rituximab (off-label) | 1000 mg i.v. at day 1 and 15 every 6–9 months | Infusion reaction within 24 days after, infections (upper and lower respiratory tract, urinary infections), Lyell Syndrome (toxic epidermal necrolysis), Stevens-Johnson Syndrome, progressive multifocal leukoencephalopathy (PML) | Severe infections, malignant diseases, severely reduced immune defense, pregnancy, breast-feeding |
| Cyclophosphamide (off-label) | Intravenous pulse therapy: 500–750 mg/m2 i.v. every 4–8 weeks under urothelial protection with mesna Oral therapy is not recommended due to side effects and rapidly high cumulative doses (maximal empiric cumulative dose 50–70 g) | Bone marrow depression, gastrointestinal symptoms, cystitis (adequate hydration!), loss of hair, liver and kidney damage, dermatitis, stomatitis, hyperuricemia elevated incidence of secondary malignancies | Kidney failure, severe infections, malignant diseases, severely reduced immune defense, pregnancy, breast-feeding |