Brief Answer:
Cold showers with oatmeal soap , benadryl tabs are fine only in mild allergies and you have to ask your psychiatrist for an alternative that works better with you .

Detailed Answer:
Hi i am Dr Ahmed Aly
thanks for using HealthcareMagic site ,
I had gone through your question and understand your concerns ..

I hope you feel better soon i think you have an allergic reaction due to these side effects you mentioned in your given history , itching and burning is not a serious side effect but i think the tachycardia or increased heart rate is a side effect you might take concerns about .
From your given history you mentioned taking benadryl which gives an antihistamine effect and decreases allergic reactions , lexapro is an antidepressant so it is contraindicated to use any kind of alcohols with it . although you can not stop it immediately to prevent withdrawal symptoms so you should decrease its dosing gradually.
For your itching you may use cold showers with the benadryl will be fine , oatmeal soap or lotion will be helpful , i think you have to tell your physician about that tachycardia as it is a dangerous sign that may need a visit to the ER if became more frequent .
You have to stop using alcohol while on that kind of medication or ask your psychiatrist to prescribe you an alternative drug that may cause no or lesser side effects ( that is the best solution in my opinion ) and tell him about these reactions .
Benadryl is usually fine in most of mild to moderate allergic reactions but it will only help with your skin reactions and not your cardiac reactions which i think it is a dangerous reaction making your allergic reaction a severe type , high oxygenation and elevation of legs may be helpful during the attack .


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