Possible Magnesium Allergic Reaction?

Patient: 21 year old Female. The past 3 weeks I have noticed this weird feeling in my knees. It feels like they are burning and I can feel the heat through my jeans. When uncovered they are bright red all the way around for a while on and off. My face also gets very hot to the touch and burning. Also my asthma was acting up around the same time this all happened. Something new I had incorporated in my life was a magnesium powder drink my doctor recommended from the health food store? I thought that was the reason so I stopped drinking it 3 days ago but everyday I am still getting the same problems. What is going on with me?

Symptoms: Burning feeling on skin of knees and face, bright red, wheezing. Feel like I can’t get any air out of my lungs.

Doctor: