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1.The history and symptoms suggest the possible cause could be infective collection.
2.Hair follicular infection / inflammation with collection with in.
3.IT needs to examine, if infective in nature and large in size, a small
incision and drainage followed by a course of antibiotics will be helpful.
4.Before you take any antibiotics - need to get examined, and assess the nature of lump, source and its extensions.
5.Suggest to see your GP, get examined, if required an
ultrasound lump - followed by the treatment.
Good luck.
Hope i have answered your query,
any thing to ask ? do not hesitate to ask.
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