Diagnosed with prostatitis & ns urethitus. Swollen lymph in groin and leftside neck. On doxy 30 days / cipro (ciprofloxacin) 6 days. Infection home but still enlarge nodes. Is this common? Neck node appeared 1night!

Prostatic is nodes. Prostatic is and urethritis treated with antibiotics and inguinal glands is okay. If you have node in the neck you need a check up by your dr.
Need more testing. Enlarged lymph nodes are usually due to infection and therefore, responds to antibiotics very well, thus, will shrink in size. Non-shrinkage of lymph nodes after a reasonable course of antibiotics calls for more testing.