Myasthenia Gravis in Acute Care

Important points

• It is crucial not to withhold MG medicines for any significant length of time, i.e. >2 hours, or to miss any doses of pyridostigmine or steroids as there is a risk of myasthenic crisis.
• Before prescribing any new medicine, check if the medicine may affect patients with MG by referring to the NHSGGC guideline Myasthenia Gravis or Lambert-Eaton Myasthenia Syndrome, medicines that may affect patients.
• High risk situations include: nil by mouth status, infection and surgical procedures.

Pyridostigmine

• It is important for pyridostigmine to be administered at exact times. Ensure no missed doses. For further guidance see NHSGGC's guideline Pyridostigmine for Myasthenia Gravis Q&A.
• Use free-format prescribing function on HEPMA if pre-fixed times are not suitable.
• Where a patient does not have an individual supply of pyridostigmine, this must be obtained urgently via pharmacy during working hours or via the local emergency cupboard, hospital co-ordinator or the on-call pharmacist via switchboard if out of hours.
• Overdose of pyridostigmine can lead to cholinergic crisis. For further guidance, refer to NHSGGC's guideline Pyridostigmine for Myasthenia Gravis Q&A.

Nil by mouth

• Administration of medication via nasogastric (NG) feeding tube is the preferred option in patients who are unable to swallow. Pyridostigmine and prednisolone (not enteric coated, E/C) tablets can be crushed and mixed with water. See NHSGGC's guideline Pyridostigmine for Myasthenia Gravis Q&A.
• Any delays in passing NG tube, or if NG insertion is not possible, seek senior medical and neurology advice as soon as possible.
• If a chest X-ray is required to confirm NG position prior to use (i.e. no aspirate), then this will be reported out-of-hours when time critical medicines (i.e. pyridostigmine) are required.

Infection

• Certain antimicrobials should be avoided (e.g. gentamicin) or used with caution. Refer to NHSGGC's guideline Myasthenia Gravis or Lambert-Eaton Myasthenia Syndrome, medicines that may affect patients.
• Do not automatically double steroid dose in the context of infection in a patient with MG (see information below).

Minor infection

1. Continue regular immunosuppressant drugs.
2. Stable MG patients may not require any change in steroid dose.

Severe infection or sepsis

1. Withhold regular immunosuppressant drugs (and discuss with MG team).
2. Consider increasing steroid dose after consulting with MG/neurology team.

Patients with stable MG can usually revert to baseline steroid dose once infection is treated (provided <3 weeks on higher dose). Patients with active MG may require slower reduction in steroid dose (consult MG team).

Patients undergoing surgical procedures

• Patients should continue with regular medication for MG pre- and post-operatively.
• Discuss on a case by case basis with an anaesthetist and MG team.