Gastroparesis is primarily caused by damage to the nerves and muscles that control the stomach's ability to empty its contents normally. The most common causes include:

• Idiopathic: In about 50% of cases, the cause is unknown (idiopathic gastroparesis).
• Diabetes: Poorly controlled diabetes is a common cause, as high blood sugar levels can damage the vagus nerve, which controls stomach muscles. This is called diabetic gastroparesis and is more common in type 1 diabetes but also occurs in type 2.
• Postsurgical: Surgeries on or near the stomach or esophagus can damage the vagus nerve, resulting in impaired stomach emptying.
• Viral infections: Certain viruses like Norwalk virus, rotavirus, or Epstein-Barr virus can trigger gastroparesis.
• Medications: Some medications, including opioids, calcium channel blockers, and certain weight loss drugs (GLP-1 agonists), can slow stomach emptying.
• Neurological disorders: Conditions such as Parkinson's disease, multiple sclerosis, and traumatic spinal cord injury can affect gastrointestinal nerve function.
• Autoimmune diseases: Autoimmune responses may damage stomach nerves and muscles.
• Other causes: Rheumatological diseases (like amyloidosis and scleroderma), hypothyroidism, and other nervous system disorders may also contribute.

Basically, gastroparesis results when the nerve signals controlling the muscles in the stomach are impaired, leading to delayed emptying of stomach contents even without any physical obstruction. This multifactorial etiology reflects why symptoms can vary and why managing underlying conditions plays a key role in treating gastroparesis. Dietary changes and avoiding certain medications are important aspects of treatment as well. If you want detailed information on specific causes or symptoms related to gastroparesis, I can provide more. Let me know! This summary is based on comprehensive medical sources outlining the causes of gastroparesis.