Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain
severe itching over the entire body and as it started 4 days after starting the intake of antibiotic Keflex containing
Cephalexin as an active ingredient seems to be most probably due to allergic reaction to Keflex and it can be a
delayed allergic reaction as when the antibiotic is taken for the first time the
antibodies can take some time to form inside the blood and when the concentration of antibodies become sufficient they can fight with the allergen, the allergic symptoms will appear..
I would suggest you to consult an Allergist and get evaluated and a thorough clinical evaluation and investigations like prick test,
Patch test, RAST test can help in diagnosis and treated accordingly..
In case if it is due to allergic reaction to Keflex you can be advised to stop taking Cephalexin and take other groups of antibiotics..
As of now you can be advised anti allergics like Levocetrizine to relieve itching..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora.