Medicated shampoo symptoms and conditions

I had a skin infection on my lower legs and was prescribed Cephalexin Monohydrate. I took it for 6 days, 4x per day, then stopped. I was supposed to continue on 2x per day for the next week.
I started itching at the top half of my buttocks and it quickly spread all over my back, chest, shoulders, arms and onto my scalp. Small lumps or hives and red blotchy skin nearly all over my old body. The itching was driving me crazy. I didn't know where to scratch or rub next.
My doctor couldn't see me for another week so I went to see another doctor who prescribed Phenergan (promethazine hydrochloride) tablets and Celestone M (betamethasone) cream.
Relief came within 24 hrs, I went through 4 days of hell and while still itchy on the 5th day, it was getting better. I also used ionil T ( a medicated shampoo ) for my scalp.
I have never been allergic to any drugs before this monster
This antibiotic should come with a warning

i started taking sulfameth/trimethoprim on 10/01/05,after taking this medication,i immediately started feelin light headed,i really didn't think it was the medication at first.after the third day of taking this medicine,i noticed my skin started getting extra dry and itchy,i started scratching my arms first because they were itching first,then my entire body started itching,i was terrified when i noticed red patches on my arms,breast,back,buttocks,legs,hands,face,neck,etc.i always pray before taking any medication,i contemplated on going to the emergency room,i said Lord there are people probably in worse shape than me,i don't want to go there and have to wait forever,and i know if i saw someone there in pain even if it was an act to get in first,i would have to let them go first,i didn't want to be digging like 90 going north.i started to pray and ask Gof to make things alright.i started rubbing myself all over with elidel,my daughters medicine,it did no good.i asked my oldest daughter to help me rub down in elidel.then i remembered that this daughter had medicated shampoo for something that looked kind of like what i had,she had the shampoo for about a year,but i prayed and asked God to help me,he did,i dampened my entire body and shampooed myself all over.it helped for a minute but i know that it's still in my body because i know the itchy feeling and the red marks all over my body.

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