I've spoke on a related issue a couple times here; rather then retype I've copied and pasted my experiences from other posts:
"A quick preface: while I have never consulted a medical professional regarding this (aside from quick chit-chat with a nurse friend) I'm pretty sure that I'm unfortunate enough to have some form of allergy to MJ. Fortunately the vapor (and smoke when I combusted) itself is completely welcome in my body, the issue for me is skin contact: grinding or handling herb can often result in a small allergic reaction for me (hives and sneezing fits, well in line with the experience I have with many other pollens). Thankfully my usage is planned around the issue and I don't have to handle herb explicitly often." (from
here)
"...If for example some MJ crumbs drop onto bare skin and get agitated, e.g. movement, skin irritation is almost a given in my case.
Needless to say my allergies seem to be only 'skin-deep.' While I've never been checked medically for what MJ smoking/vaping/ingesting does to me, I'm doing just fine in that arena."
here)
"Re: coping with the skin allergy. If I'm going to be preparing herb with my hands I will put on disposable vinyl gloves available at the pharmacy (vinyl better than latex for this application because of the smell and occasional powder that the latter contain) and do my best to keep the herb away from arms/chest/etc. My significant other is also very helpful in prepping for vape time. Beyond that I've come to really prefer using a bong/bubbler to stop any particulate from entering my throat (and the possibility of that awful wheeze/rattle!)." (from
here)
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