Hi, welcome to the forum, your history is suggestive of that you are having drug allergy to morphine
. Some patients have
reported to have
more than 10%), rash and development of hives.
The possibilities for allergy are due to presence of Phenanthrene in opioids. You can even develop hypersensitivity reactions to other phenanthrene derivative opioid agonists (codeine, hydrocodone, hydromorphone, levorphanol, oxycodone, oxymorphone).