When Symptoms Appear Overnight: Understanding PANS and PANDAS

One day, your child is their usual self. The next, they seem overwhelmed by sudden anxiety, obsessive rituals, tics, or intense rage that appears to come from nowhere. Or perhaps it’s happening to you: a brain fog that settles in overnight, or the abrupt return of symptoms you thought were finally behind you.

When you seek help, you may be told it’s “just anxiety,” “just a phase,” or given a psychiatric label that doesn’t account for how suddenly everything changed. But you know something is different. Trust that instinct—you are not wrong to keep asking questions, looking deeper, and seeking answers.

Defining PANS and PANDAS

PANDAS—Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections—describes the sudden onset or dramatic worsening of neuropsychiatric symptoms following a strep infection. In susceptible individuals, the immune response intended to fight the infection may become dysregulated and contribute to inflammation that affects the brain and nervous system.

PANS—Pediatric Acute-onset Neuropsychiatric Syndrome—is the broader clinical framework. It describes a similarly abrupt onset of symptoms, but the trigger is not limited to strep. Potential contributors can include infections such as Lyme disease, mycoplasma, and viral illnesses, as well as other inflammatory stressors, including environmental exposures such as mold. Although these conditions were initially described in children, abrupt, infection- or inflammation-associated neuropsychiatric flares can also occur in adolescents and adults.

What often distinguishes PANS and PANDAS is the speed of onset. A child who seemed well on Monday may, within days, develop intense OCD behaviors, separation anxiety, emotional lability, tics, handwriting regression, urinary frequency or bedwetting, food restriction, or sleep disruption. In adults, the pattern may look like a sudden return or escalation of anxiety, obsessive thoughts, mood symptoms, cognitive changes, or neurologic complaints after a period of relative stability.

Flares may also follow a seasonal pattern. Spring and fall can be higher-risk periods for some individuals, potentially due to shifts in viral circulation, strep exposure, allergies, immune activity, and environmental triggers.

The Hidden Triggers We Look For

Mold is one of the most overlooked inflammatory triggers—particularly when there is hidden water damage in a home, school, or workplace. Mycotoxins and other mold-related exposures may affect the nervous system and invoke immune dysregulation, potentially contributing to neuroinflammation and symptom flares in susceptible individuals.

Co-infections like Mycoplasma or viruses can work to highjack and dysregulate T helper cell function leading to a persistent immune activation in the brain that manifests in neuropsychiatric symptoms/brain inflammation. In practice, I have also seen patients with quantitative spike levels >2500 struggling with cognitive, mood and signs of acute onset without a predominant co-infection identified.  

Lyme disease also warrants careful consideration, especially when symptoms have been persistent, relapsing, or difficult to explain. The original tick exposure may have occurred years earlier and been dismissed as an ordinary bug bite. When present, Borrelia infection and associated tick-borne infections such as Bartonella or Babesia may contribute to prolonged immune and neurologic symptoms. A later stressor—such as another illness, major life change, or seasonal shift—can then coincide with a more noticeable behavior regression.

Why It Gets Missed

This is one of the most under-recognized, misdiagnosed conditions we see. Because the symptoms look psychiatric on the surface, families are routinely sent toward behavioral labels or medication trials that never touch the actual cause: an infection that has inflamed the brain. Every month spent chasing the wrong diagnosis is a month the underlying inflammation goes untreated. If someone in your life – child or adult – has a sudden, dramatic shift in mood, behavior, or motor symptoms, that deserves real investigation, and a deeper look. It is critical to find a provider who is genuinely trained to recognize and treat PANS/PANDAS.

Getting Closer to an Answer: Testing

Diagnosis is based on the clinical picture, symptom history, physical exam, and thoughtful evaluation for possible infectious, immune, inflammatory, and environmental contributors. Standard bloodwork often misses PANS and PANDAS. Here is what we look for:

The Cunningham Panel: A specialty test that measures several anti-neuronal antibodies (attack the brain) and immune markers associated with neuropsychiatric symptoms. Results should always be interpreted alongside the patient’s clinical history and presentation.

ASO and anti-DNase B titers: Blood markers that can provide evidence of a recent or prior exposure to group A strep.

IgG/IgA total and subclass testing: This evaluates the total serum IgG and IgA.  IgG subclasses—IgG1, IgG2, IgG3, and IgG4— can be useful when a patient has frequent or recurrent infections despite a normal total IgG level.

Comprehensive stool testing: In some cases, gastrointestinal testing may help identify bacterial, parasitic, yeast, or inflammatory factors that are not apparent on standard bloodwork. Sometimes organisms driving inflammation shows up in the gut when we don’t see it on a blood test. 

PANS and PANDAS are rarely a simple, one-trigger picture. A patient may have a history of strep exposure alongside immune dysfunction, chronic sinus or gastrointestinal inflammation, environmental exposures such as mold, or possible tick-borne illness. If care focuses only on the most obvious finding while other contributing factors remain unaddressed, symptoms may persist or repeatedly flare.

Comprehensive testing is how we find out exactly which toxin(s)/infection(s) are driving a specific person’s inflammatory and immune dysregulation, so treatment can address the whole patient instead of chasing a symptom.

Why Antibiotics May Not Be Enough

Antibiotics can be an important part of treatment when there is evidence of an active bacterial infection. However, they may not address every factor contributing to PANS/PANDAS symptoms or recurrent flares. A comprehensive plan may also consider immune regulation, inflammation, sleep, nutrition, gastrointestinal health, and ongoing sources of infection or exposure.

The gut-brain connection is one area that may deserve attention. The intestinal lining acts as a barrier between the digestive tract and the rest of the body. When that barrier is disrupted, immune signaling and inflammation may increase. Some clinicians also evaluate markers associated with intestinal permeability, such as zonulin, although these results should be interpreted carefully and in the context of the whole clinical picture. Supporting gastrointestinal health is typically part of a broader plan for reducing inflammation in our practice.

Oral health matters, too. The mouth, teeth, gums, tonsils, and sinuses can sometimes serve as ongoing sources of inflammation or infection. A negative throat swab does not always rule out every possible source of concern, particularly when symptoms are persistent or recurrent. Consistent brushing, flossing, routine dental care, and prompt attention to gum disease, dental infections, or chronic sinus symptoms can help reduce this potential burden.

For some patients, providers may also recommend supportive measures such as sinus irrigation- reduce what can travel up the olfactory nerve into the brain, oral antimicrobial measures with support to lyse biofilms that can surround resistant organisms, and oral probiotics. These options are not replacements for medical or dental treatment, but they are typically considered as part of an individualized plan. 

Lasting improvement often requires looking beyond a single trigger. That may include identifying and treating active infections, reducing significant environmental exposures, addressing nutritional and gastrointestinal concerns, and supporting the body’s ability to regulate inflammation. The goal is not simply to suppress symptoms during each flare, but to understand why flares continue to occur and reduce the factors that may be keeping the immune system from developing a solid adaptive response.

Treatment should be individualized and guided by an appropriately qualified clinician. Some patients may benefit from anti-inflammatory or immune-modulating therapies, including medications such as low-dose naltrexone or, in select acute situations, steroids. Steroids should only be seen as a bridge while the real work of healing the immune system happens underneath.

You Deserve Care That Looks Beyond the Symptoms

If this sounds like your child—or like you—you deserve to feel heard, believed, and supported. You also deserve a care partner who looks beyond the most visible symptoms, takes the time to understand the full clinical picture, and works with you to create a thoughtful, step-by-step plan.

Healing is not always quick or linear, but meaningful progress is possible. With the right support, careful investigation, and an individualized approach, it is possible to move from constantly managing flares toward greater stability and restoration.

A helpful starting point is the PANDAS Physicians Network, which offers resources for locating providers familiar with the evaluation and treatment of PANS/PANDAS. There is also the Medical Academy of Pediatric Special Needs where you can find a FELLOW trained to properly treat this kind of condition.  If you are ready to discuss what a personalized roadmap could look like for you or your family, we are here to help.