Buspirone for Early Fullness: Four BESST Trial Checks

Getting full after a few bites and feeling excessively full after a meal belong in the appointment description. Record which happens, approximately when, and whether it prevents you from finishing food.

Confirm what diagnosis was studied

BESST randomized 96 adults with moderate-to-severe early or post-meal fullness; 88 were women. Half had delayed stomach emptying. They received buspirone 10 mg or placebo three times daily for four weeks.¹

Symptoms alone do not establish gastroparesis. The AGA’s 2025 guidance favors four-hour gastric-emptying testing over two hours or less when evaluating suspected gastroparesis. Ask which diagnosis your testing supports.²

Read the main result first

The main 0–5 fullness score showed no significant benefit: adjusted buspirone-minus-placebo difference −0.11 points (95% confidence interval −0.68 to 0.45; P=.69). Eighteen participants lacked week-four outcomes; the analysis estimated missing values. NIDDK funded BESST; authors declared no competing interests.¹

Treat the bloating signal as provisional

The apparent difference between severe-bloating and milder-bloating subgroups had P=.003, becoming P=.07 after Bonferroni correction for multiple comparisons. It does not establish whom to prescribe buspirone for.¹

The paper calls subgroups prespecified; its discussion and protocol call the analyses post hoc. This terminology conflict adds caution.¹³

The AGA suggests against buspirone as first-line gastroparesis treatment, a conditional recommendation based on very-low-certainty evidence. Its comment allows an individual choice through shared decision making when potential fullness or bloating improvement is especially valued. That is a prescribing discussion, not a confirmed subgroup benefit.²

Review prescribing limits and interactions

The US label covers anxiety disorders or short-term anxiety symptoms. Digestive use is off-label. Review the complete medicine list, including antidepressants and migraine treatments. The label warns about potentially life-threatening serotonin syndrome and contraindicates combinations with MAO inhibitors, including starting buspirone during linezolid treatment. Do not arrange a medication washout yourself.⁴

Dizziness and drowsiness can occur. Avoid driving or dangerous machinery until you know how buspirone affects you. The label also cautions against alcohol and large amounts of grapefruit juice, and does not recommend use with severe liver or kidney impairment.⁴

The Belly Clock in Bloated by Dinner records meals, symptom timing and medicines. Bring that account with the test results and ask which symptom the proposed treatment should change, by how much, and when it will be reviewed.