Magnesium stearate allergy

Question:

10/31/2018
65 year-old female with history of Bahcet’s syndrome with blistering skin disease and Mono Neuritis multiplex, presented with severe generalized urticaria with itching and stabbing pain in certain parts of her body for 5 months. All her meds including IvIg were stopped with resolution of her symptoms. While reintroducing MgOxide, she had recurrence of her same symptoms of urticaria and stabbing pain and so she was taken off MgOxide and restarted on her IvIg without any symptoms. She then had hives with crab and fish chips, and her skin testing was negative with crab, all shell fish and fish. These symptoms were thought to be from Mg content of sea foods. When she restarted her other meds she had mild urticaria and stabbing pains. While going through all ingredients of her medications, it was found that many of tablets contained Mg Stearate and she stopped all those tablets with complete resolution of all her symptoms. She was tried on Mg Hydroxide containing antacids and she is tolerating them well, concluding that Mg Stearate is the cause of her Urticaria. MgOxide tablets, also contained Mg Stearate.

Are you aware of any blood tests or skin testing protocols for Mg Stearate? Patient has read about it on website which recommend blood tests and skin tests for Mg Stearate. She feels comfortable having testing backed diagnosis moving forward as she is now afraid of taking any tablets.