The rash and knots are likely to be related. The knots seems to be enlargement of the lymph nodes due to rash. And the rash seems to be urticaria. This can be due to birth control. The major causes of urticaria are;
1) Foods or food additives
2) Inhalation, ingestion of, or contact with antigens
3) Drug reactions
4) Infections: bacterial, fungal, viral, and helminthic/parasites
5) Insects (papular urticaria)
6) Cold urticaria
7) Aquagenic (water) urticaria
8) Solar (Sun) urticaria
9) Chronic autoimmune (problems of immunity) urticaria
10) Chronic idiopathic (unknown reason) urticaria
Oral anti-histaminics are effective and you may try Benadryl.
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