This study investigates WecProB (Bifidobacterium animalis subsp. lactis and Lacticaseibacillus rhamnosus) to evaluate their potential to improve symptoms and safety in children with ADHD.

Inclusion Criteria:

1. Diagnosis of ADHD per DSM-5 criteria;
2. Age 6-12 years, gender-neutral;
3. IQ >70 on intelligence testing;
4. Participant/guardian comprehension and voluntary consent.

Exclusion Criteria:

1. Those with a clear history of other serious neurological diseases, such as epilepsy, head trauma, encephalitis or meningitis, etc.;
2. Have taken antibiotics, probiotics or immunosuppressants within one month before starting the experiment;
3. Ongoing special diet, such as ketogenic diet, etc
4. BMI higher than the 90th percentile or lower than the 10th percentile for children of the same age and sex;
5. Those who have had symptoms of respiratory or digestive tract infection in the past month, such as fever, cough, diarrhea, etc.;
6. Those who have had inflammatory bowel disease in the past, such as ulcerative colitis, Crohn's disease, etc.;