1. Gastric emptying study
2. Colonic transit time test
3. Small bowel follow through/transit test
4. Anorectal manometry test
5. Abdominal x-ray to look for colonic stool burden

1,2, and 3 are for motility issues. 4 and 5 for pelvic floor dysfunction.

Doctors are assholes and won't take you seriously. Fight for them to give you these tests. SIBO won't go away until you fix the constipation, or it'll keep coming back, or your numbers will be low but bloating and nausea will continue.

Lastly, stay strong. You are your best advocate.

Motility and pelvic floor issues can really wreak havoc on your parasympathetic nervous system, so treating these first may be necessary if you are like many people on this sub who are not getting better despite multiple rounds of rx and natural antibiotics.