Please see a doctor or urologist immediately for an in-person evaluation. A continuous erection lasting six months is medically impossible without causing severe, permanent tissue damage. However, if you are experiencing recurrent, prolonged erections, this requires urgent urological assessment. The itching and discomfort you describe are likely unrelated to Viagra and are more commonly caused by a localised issue, such as a fungal infection (balanitis), contact dermatitis, or a skin irritation. Do not attempt to self-medicate. A physician must physically examine the area to determine the exact cause and prescribe the appropriate antifungal, steroid cream, or other targeted treatment.