Unisom severe allergic reaction

I'd been taken sleeping pills such as Sominex, Unisom, and Melatonic for about a year... went pretty much cold turkey now for 6 months due to a very strange allergic reaction. The first time this happened I had just gotten back from work and had eaten out at a favorite Chinese restaurant of mine. Anyways I get home and take a Unisom and start reading a book to go to bed. I then experience the following symtoms (symptoms);

note: Keep in mind I thought I had been food poisoned the first time this happened...

Elevated Heart rate (Tachycardia)
Confusion
Trouble breathing
Muscle Spasms
Nervousness
Dry Mouth


I called the hospital and showed up around 1-2 hours later by ambulance, I didn't know what was wrong with me. Hospital said I had Anxiety/Stress+Tachycardia gave me Ativan and I blacked out and woke up in my bed the next morning. The symptoms  increased over time as well, by the time I got to the hospital my legs, chest, back, glutes.. everything was twitching. My mouth was extremely try, I got a IV and started urinating a lot.

Fast Forward  6 months later, I'm deployed... by some Unisom take 1 pill all of a started feeling really sick like something was brewing nasty inside me. I immediately find someone and tell them to take me to the on-base hospital and I experience the same side effects but this time I had pretty much immediate help and I feel the same way. But I recover  a few hours later, drank a ton of water and got another IV. I KNEW it was UNISOM this time...

How does something like this happen? How rare is this? Apparently I developed a allergic reaction to this med now...

[Paderla Anitha, DNB]

Hello and hope you are doing well.

It could indicate a allergic reaction. As repeated episodes have occurred with consumption of the same medication. Allergic reactions are mediated by IgE antibodies, which are released on exposure to a particular allergen. These in turn activate mast cells and lead to a local response or systemic anaphylaxis. It can occur at anytime. Allergic testing may be worth looking into. Here an allergy specialist may confirm the allergic reaction and can further help to desensitize you.

Hope this helped and do keep us posted.

[kmain]

I will do, thanks for the response. It was hard to find any information on this besides a couple things on webmd that said having severe side effects were rare.

[Paderla Anitha, DNB]

Hello and hope you are doing well.

Once an allergic reaction is known to occur, the allergen is best avoided. Discuss your symptoms with your consulting doctor he may change the medication.  

Hope this helped and do keep us posted.