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treatment, which mainly ameliorate the clinical Methylprednisolone has a more rapid therapeutic effect
symptoms, particularly for the initial treatment of in MG treatment than prednisone for 1.25 fold, as the
newly diagnosed patients of MG and as a single agent former needs not to be activated in liver. Furthermore,
for long-term treatment of cases of mild MG, although methylprednisolone has a higher immuosuppressive
[8]
it is not recommended. Dose should be individualized effect (18 fold) than prednisone since the former
and combined with other immunosuppressive drugs. has a higher affinity to corresponding receptors.
Pyridostigmine bromide is the most commonly used Such property produces lesser side effect and steady
cholinesterase inhibitor for MG treatment. Side effects concentration, which is more suitable for those MG
include nausea, diarrhea, stomach cramp, bradycardia patients with compromised hepatic function.
and increase of oral and respiratory secretions. In
China, the maximum oral dosage per day is 480 mg Intensive monitoring is necessary for treatment with
and three to four times. glucocorticoids. There are approximately 40-50%
MG patients experiencing transient aggravation and
Immunosuppressive drugs possibly myasthenic crisis. Thus, extra cautions are
used for those with severe symptoms and higher risk
Glucocorticoids: it is a potent anti-inflammatory and of myasthenic crisis. It is also highly recommended
immunosuppressive agent, efficient in MG treatment to administer calcium and bisphosphonates agents
with significant improvement in 70-80% cases. The for preventing osteoporosis and antacid drugs for
[9]
commonly used glucocorticoids for MG treatment preventing gastrointestinal complications. There is
include prednisone, methylprednisolone and also chance to develop steroid myopathy. Chronic
dexamethasone. The indications are as followed: 0.5- usage of glucocorticoids will increase appetite, body
1.0 mg/kg/day or 20 mg/day prednisone at morning. weight and central obesity, hypertension, high blood
According to the glucocorticoid dose conversion, 5.0 glucose, cataract, glaucoma, endocrine disorders,
mg prednisone is equal to 4 mg methylprednisolone mental disorders, osteoporosis, osteonecrosis and
and 0.75 mg dexamethasone. Dosage should be other alimentary disorders.
increased by 5.0 mg every three days till 60-80 mg.
Improvement could be observed in 2 weeks, which Azathioprine: this is the first line agent for MG for both
will be significant at 6-8 weeks after treatment. For ocular and generalized forms. Azathioprine could also
severe cases, with the adequate communication be co-prescribed with glucocortioid so that in short
between physician and patients, patients can term, the dosage of glucocorticoid could be reduced.
receive corticosteroid therapy under mechanical At the initial stage of treatment, glucocorticoid and
ventilation. Corticosteroid therapy will be achieved azathioprine provide a better treatment than single
by continuous intravenous perfusion of 1,000 mg/ use of glucocorticoid or azathioprine. For MG patients
day methylprednisolone for 3 days. Afterward, who are older than 3 year-old and at teenages,
dose should be decreased to 500 mg/day for 2 days. azathioprine could be co-prescribed when therapies
During this, methylprednisolone could be replaced with cholinesterase inhibitors and glucocorticoid are
by dexamethasone (10-20 mg/day) for 1 week. After not desirable. Azathioprine should be administered in
corticosteroid therapy, patients should take prednisone a low dose and gradually increased as this agent could
or methylprednisolone at morning as aforementioned. elevate the hepatic enzyme activities and inhibit the
Dosage of prednisone and methylprednisolone should marrow function. Effect will be seen 3 to 6 months
be fine adjusted or individualized according to after administration while the peak effect will reach
patients’ conditions. If MG conditions are improved, after 1 to 2 years. About 70-90% MG patients are
dosage could be gradually reduced after 4-16 weeks. significantly improved after this treatment.
Typically, prednisone could be reduced by 5-10 mg
every 2-4 weeks, and then 5 mg every 4-8 weeks when Instruction is as followed: 1-2 mg/kg/day for children
dose is or lower than 20 mg. According to different and 2-3 mg/kg/day for adult; spilted into 2-3 times oral
cases, patients could receive the lowest optimal dose dose per day. Chronic usage is allowed until adverse
every other day. Too vigorous reduction of drug will effect and intelarance are seen. About 7-10 days after
worsen the MG conditions. azathioprine administration, blood test and hepatic
functions of patients should be monitored. Side
In adult generalized MG and certain ocular MG effects includes specific flu symptoms, reduciton of
cases，glucocorticoids should be reduced or terminated white blood cells and plalete, alimentary symptoms,
if there are any fluctuation or aggravation. In order eaken hepatic function and loss of hair. Chronic users
to provide an optimal therapy, it is recommended to of azathioprine should take blood test every 2 weeks,
co-administer other immunosuppressants, such as tests of hepatic and renal functions every 4 weeks. If
azathioprine, cyclosporine A or tacrolimus. possible, gene screening of purine methyltransferase

Neuroimmunol Neuroinfammation | Volume 3 | Issue 1 | January 20, 2016 5