Gastroesophageal reflux disease (GERD): This condition is characterized by the backflow of stomach acid into the esophagus, which can cause irritation and lead to symptoms like hiccups and diarrhea due to the body's attempt to expel the irritant.

Irritable Bowel Syndrome (IBS): A common disorder that affects the large intestine, causing a variety of symptoms including diarrhea, abdominal pain, and changes in bowel movements. Hiccups could be associated with the abdominal discomfort or gas.
Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause chronic diarrhea and abdominal pain. Hiccups might occur due to the inflammation affecting the diaphragm or as a side effect of medications.
Giardiasis: An intestinal infection caused by the parasite Giardia lamblia, leading to prolonged diarrhea. Hiccups could be a less common symptom associated with the infection.

Pneumonia: Although less likely, pneumonia can cause hiccups due to irritation of the diaphragm. Diarrhea might not be a direct symptom but could occur due to antibiotic use or a viral cause of pneumonia.
Myocardial Infarction: In rare cases, hiccups can be a symptom of a heart attack, especially in women. Diarrhea could be associated with the stress response or medications used during the event.
Medication Side Effects: Certain medications can cause both diarrhea and hiccups as side effects. It's crucial to review any new medications started around the time symptoms began.

Eosinophilic Gastroenteritis: A rare condition characterized by the presence of eosinophils in the gastrointestinal tract, leading to symptoms like diarrhea and potentially hiccups if the stomach or esophagus is involved.
Gastroparesis: A condition where the stomach takes too long to empty its contents, which can cause nausea, vomiting, and diarrhea. Hiccups might occur due to the abnormal stomach function or associated gastroesophageal reflux.