What casues red bumps on back of the calf?
Allergic contact dermatitis is a possibility
welcome to HCM.
I have read your query and understood you concern.
I have seen the attached pic also. Thanks for the same.
It seems that you have got allergic contact dermatitis. It is an allergic reaction to some allergen in contact with skin.
I usually advise my such patients to apply a combination cream of antibiotic and moderate potency steroid (like clop G cream) over the lesions twice daily for 7-10 days.
Additionally oral antihistaminics like levocetrizine 5mg is advised in night time for few days.
Avoid contact with harsh soap and synthetic clothes.
I hope it helps. If you have any further query, you may ask me.