PANS and PANDAS When Infection Triggers Sudden OCD, Anxiety and Eating Disorders
- Mar 25
- 6 min read
I'm an international holistic health practitioner, specialising in supporting individuals with ADHD, autism, allergies, sleep issues, and gut problems using natural medicine. I help people uncover and treat root causes so they can reclaim their health and thrive.
A child who was thriving suddenly refuses to eat. Within days, they are overwhelmed by intrusive thoughts, extreme fear, or relentless hand washing. They may develop motor tics, explosive rage, crippling separation anxiety, or begin wetting the bed after years of dryness. Parents often hear the same explanations: anxiety, obsessive compulsive disorder (OCD), an eating disorder, behavioural regression, and stress.
But sometimes, the story is immunological. Two conditions, Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) and Pediatric Acute-onset Neuropsychiatric Syndrome (PANS), describe a pattern in which infection appears to trigger sudden and dramatic neuropsychiatric symptoms.
For families living through it, the change can feel as though a switch has been flipped overnight. Some parents may have to stop working to support their children in the home because school, sports and social outings become insurmountable events for the child.
What are PANS and PANDAS?
PANDAS was first described in children who developed obsessive-compulsive disorder (OCD) or tic disorders following a streptococcal (Strep) infection, such as strep throat or scarlet fever. The defining feature is a severe and abrupt onset, often accompanied by a relapsing pattern linked to infections, where the symptoms can become more severe with multiple recurrences.
PANDAS develops in children before puberty who've had a strep infection within the last few months. In acute situations where symptoms have lasted over a week, a blood test can identify if the child has had a strep infection. A PANS or PANDAS diagnosis requires a thorough evaluation because specific antibodies have not been discovered by researchers. PANS is a broader diagnosis. It includes acute-onset OCD or severely restricted food intake triggered by various infections or inflammatory processes, not only streptococcus. Viral infections, environmental disorders like Lyme disease, and other immune stressors have been implicated.
Here’s how PANS and PANDAS might show up:
Sudden-onset OCD
Eating disorder
Motor or vocal tics
Extreme separation anxiety and panic attacks
Moodiness, rage, intrusive-catastrophic thoughts
Developmental regression, decline in academic performance,
Urinary frequency or bed wetting
Sensory hypersensitivity or hyperactivity
In PANS, food restriction is particularly significant. Unlike classic anorexia nervosa, it is often not driven by body image concerns. Instead, children may suddenly fear choking, vomiting, contamination, or poisoning. The onset is rapid, sometimes within days, in a child who previously ate normally.
Anxiety, fear, and the survival brain
One of the most distressing aspects of PANS and PANDAS I have seen clinically is the intensity of fear. Children cling desperately to parents, refuse to sleep alone, express sudden fears of death, clean obsessively, or develop new phobias without prior history.
From a neuroimmune perspective, inflammation affecting the basal ganglia and limbic system may dysregulate fear circuitry and dopamine signalling. The child appears locked in a survival response: fight, flight, or freeze.
The immune-brain connection
Research suggests immune responses can mistakenly target the brain through molecular mimicry. Where antibodies produced against streptococcal bacteria mistakenly target brain tissue. This can contribute to inflammation in regions responsible for behaviour regulation, emotional control and movement.
This can disrupt mood, behaviour, and cognition, highlighting the deep connection between immune health and brain function.
While this immune-mediated model is supported by growing research, the exact mechanisms underlying PANS and PANDAS remain an area of ongoing investigation.
Why misdiagnosis happens
Because symptoms include anxiety, OCD, rage, and restricted eating, children are often first referred for psychiatric evaluation.
Psychological care is vital. But when the onset is sudden and dramatic, an immune component should be considered, especially if there was a recent infection or a rapid and extreme personality change.
The overlooked role of folate in neuroimmune health
Folate plays a critical role in neurotransmitter production, methylation, and brain function, with deficiencies linked to a range of neurological and psychiatric symptoms.
Functional folate deficiencies may contribute to anxiety, OCD, and cognitive symptoms, particularly where transport into the brain is impaired. Supporting folate pathways can be an important component of a comprehensive neuroimmune treatment approach.
An integrative clinical approach
From a holistic standpoint, PANS and PANDAS represent immune dysregulation expressed through the nervous system. They are multi-system conditions requiring a layered and individualised approach.
An integrative approach may consider strengthening the immune system with antimicrobials, gut microbiome balance, optimising nutritional status, correcting nutritional deficiencies, and reducing inflammation. The gut immune brain axis is central in complex neuroimmune conditions.
In homeopathic practice, treatment is individualised. Nosodes remedies prepared from disease material are sometimes used when a clear post-infectious pattern is present. For example, Streptococcinum may be considered in cases where OCD, perfectionism, self-critical thinking, and rage emerge following streptococcal infection. In addition, homeopathic support remedies may also include individually selected remedies to reduce acute fear and anxiety, such as Arsenicum album or Aconite, or homeopathic immunoglobulin or thymus gland to support the immune system.
When parents aren’t believed
A consistent theme in these cases is the experience of the parent who first notices the shift. One mother described it simply, “This is not my child.” Because the symptoms appear psychiatric, families may be told it is behavioural or stress-related. When diagnostic tests are inconclusive or clinicians are unfamiliar with immune-triggered syndromes, parents can feel dismissed.
When behaviour shifts overnight, parental concern is not overreaction. It is pattern recognition. And in complex neuroimmune conditions, early recognition matters.
A wider health lens
PANS and PANDAS highlight something essential: the immune system and the brain are in constant conversation. Sudden obsessive-compulsive behaviours. Extreme fear. Acute food refusal. Rage. Regression. Sensory issues. When behaviour changes suddenly, looking beyond psychology to immune function can open new pathways for understanding and care. These symptoms may not always originate in the psyche alone. In some cases, they are inflammatory signals from an immune system in distress. This broader perspective allows for more compassionate, targeted, and effective support for children and families navigating these complex conditions.
Holistic care that looks at the root cause and treats it at the source of the problem, rather than suppressing the symptoms or giving psychiatric medicine for life, because it is diagnosed as being “ all in their head”.
Work with me
If your child has experienced sudden behavioural, emotional, or neurological changes, you don’t have to navigate this alone. I offer personalised consultations to uncover the root causes and create a tailored plan for recovery that fits your family’s unique needs. You can book a free 15-minute introductory call to discuss your child’s case and next steps, or book an initial consultation with me.
This article is for educational purposes and does not replace individual medical advice.
Read more from Tina Horrell
Tina Horrell, Natural Health Care Practitioner
Tina Horrell is an integrative homeopath and naturopath with over 25 years of international experience. Tina supports individuals and families with a range of health concerns, specialising in autism, ADHD, allergies, gut issues, and sleep problems. She also offers targeted detox programs for heavy metals and environmental toxins. Her work blends homoeopathy, nutrition, herbal medicine, and detoxification to restore clients' balance and vitality, mentally, emotionally, and physically. Tina consults with clients worldwide via online video sessions and is a regular health writer for Brainz Magazine.
References:
National Center for Biotechnology Information (NCBI). (2023). Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS).
National Institute of Mental Health (NIMH). (2024). PANS and PANDAS: Questions and Answers.
Biological Psychiatry. Swedo, S.E. et al. (1998). Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections: Clinical description of the first 50 cases. Biological Psychiatry, 44(1), pp. 49-63.
American Journal of Psychiatry. Murphy, T.K. et al. (2014). Clinical factors associated with pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections. American Journal of Psychiatry.
Journal of Neuroimmunology. Cunningham, M.W. (2012). Streptococcus and rheumatic fever: Molecular mimicry and autoimmunity. Journal of Neuroimmunology.
PANDAS Physicians Network. (2022). Immunological Features of PANS/PANDAS.
Autoimmune Institute. (2023). PANS, PANDAS, and Autoimmunity.
Frontiers in Psychiatry. Frankovich, J. et al. (2017). Clinical management of pediatric acute-onset neuropsychiatric syndrome: Part I, psychiatric and behavioral interventions. Frontiers in Psychiatry.
Journal of Child and Adolescent Psychopharmacology. Thienemann, M. et al. (2017). Clinical management of pediatric acute-onset neuropsychiatric syndrome: Part II, use of immunomodulatory therapies. Journal of Child and Adolescent Psychopharmacology.
Molecular Psychiatry. Reynolds, E. (2006). The neurology of folic acid deficiency. Molecular Psychiatry, 11(2), pp. 130–138.
American Journal of Clinical Nutrition. Obeid, R. et al. (2007). The role of folate in neurological and psychiatric disorders. American Journal of Clinical Nutrition, 85(3), pp. 907-913.
