Those patients taking metformin are advised to not resume that medication until 48 hours post contrast exposure due to a rare, but potentially life-threatening, risk of lactic acidosis after contrast exposure. The risk of lactic acidosis is primarily related to the degree of renal impairment not an interaction between metformin and the contrast media. Thus if a patient is in need of urgent imaging with iodinated contrast, or gadolinium in a usual dose range, and is not in acute kidney injury, stage IV or stage V chronic kidney disease, or has a procedurally related increased risk of kidney injury no extra precautions are explicitly necessary to protect renal function pre- or post-procedure.
The National Heart, Lung, and Blood Institute (NHLBI) recommended dosing for systemic prednisone, prednisolone, or methylprednisolone in pediatric patients whose asthma is uncontrolled by inhaled corticosteroids and long-acting bronchodilators is 1–2 mg/kg/day in single or divided doses. It is further recommended that short course, or "burst" therapy, be continued until the patient achieves a peak expiratory flow rate of 80% of his or her personal best or until symptoms resolve. This usually requires 3 to 10 days of treatment, although it can take longer. There is no evidence that tapering the dose after improvement will prevent a relapse.
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