My husband got bitten by brown recluse just at the base of his pennise. He had antibiotic treatment at the hospital. But local doctors dont really have experience with spider bites
to open wounds and secondary infections. You may apply a mild steroid cream like 1% hydrocortisone cream and take OTC anthistaminics like benadryl or Claritin. In case of intense itching
an oral dose of anti-histamine like Dimetapp, Chlortrimeton is very effective in relieving itch. Once the itch stops, you will stop scratching as well and the healing will take place faster.
But if the symptoms do not improve or worsen then please consult a dermatologist a course of antibiotics and a jab of steroid may be needed to stop the inflammation. Also your husband has to check his tetanus immunization schedule.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.