The most important difference is the timeline. Traditional OCD develops gradually — symptoms emerge over weeks or months, starting mild and becoming more entrenched over time. PANS and PANDAS OCD does not work that way. It arrives suddenly, often dramatically, in a child with no prior history. Parents frequently remember the exact date. The OCD also typically arrives alongside other symptoms — separation anxiety, food refusal, sleep disruption, rage, urinary frequency — that would not be expected with primary OCD alone. That combination of sudden onset and multiple simultaneous symptoms is what points a clinician toward PANS or PANDAS rather than primary OCD. Documenting the timeline your child's symptoms followed is one of the most clinically useful things you can bring to a provider appointment.