The International Brain Tumour Alliance (IBTA) is a global network that advocates for brain tumour patients and their caregivers, providing support, raising awareness, and sharing information about brain tumours and related challenges.

iCare.org provides expert guidance, digital tools, and resources to support seniors and caregivers affected by Alzheimer's disease.

ican is a support group for families dealing with anophthalmia and microphthalmia, providing resources and connections to other families and medical professionals.

The IETF provides awareness, education, support, and research for individuals affected by essential tremor, a common neurological condition.

The International Federation Spina Bifida and Hydrocephalus advocates for the rights and health of individuals with Spina Bifida and Hydrocephalus, focusing on prevention, access to healthcare, and raising awareness.

The IFOPA supports individuals with fibrodysplasia ossificans progressiva (FOP) and their families through education, advocacy, and funding research for a cure.

The International Foundation for CDKL5 Research supports individuals affected by CDKL5 Deficiency Disorder (CDD) by providing resources, advocating for research, and connecting patients and families.

The International Foundation for Gastrointestinal Disorders (IFFGD) provides resources, support, and education for individuals affected by gastrointestinal disorders, focusing on research, awareness, and patient advocacy.

The International FOXG1 Foundation raises awareness and provides support for families affected by FOXG1 Syndrome, offering resources and a community for those impacted by this rare genetic condition.

The International FOXP1 Foundation supports families and individuals affected by FOXP1 syndrome, a rare genetic disorder, by sharing knowledge, encouraging research, and raising awareness.

The International FPIES Association advocates for individuals affected by Food Protein-Induced Enterocolitis Syndrome (FPIES) by providing education, support, and promoting research to improve diagnosis and treatment options.

The International Hearing Society represents hearing healthcare professionals worldwide, providing resources, advocacy, and education to enhance the practice and profession of hearing health.

The International Hyperhidrosis Society is a global non-profit organization dedicated to improving the lives of individuals affected by hyperhidrosis, providing education, support, and resources related to excessive sweating.

The International League Against Epilepsy is a global organization dedicated to improving the lives of individuals affected by epilepsy through research, education, and advocacy.

The International Mosaic Down Syndrome Association (IMDSA) provides support, information, and research for families and individuals affected by mosaic Down syndrome, offering services such as online support groups, a toll-free hotline, and educational resources.

The International OCD Foundation supports individuals affected by Obsessive Compulsive Disorder (OCD) through research, treatment access, and community awareness initiatives.

The International Pain Foundation (iPain) supports the chronic pain community by providing education, awareness, and access to care resources, while fostering a sense of community among patients.

The International Painful Bladder Foundation is a non-profit organization that promotes knowledge and awareness of interstitial cystitis, bladder pain syndrome, and related disorders among patients and health professionals.

The International Paruresis Association (IPA) is a nonprofit organization that supports individuals suffering from paruresis, a social phobia that makes it difficult to urinate in the presence of others, by providing workshops, support groups, and resources.

IPOPI is an international non-profit organization that supports individuals with Primary Immunodeficiencies (PIDs) through awareness, early diagnosis, and care initiatives.