Capsaicin for Hyperemesis
Capsaicin is NOT recommended for hyperemesis gravidarum (pregnancy-related hyperemesis), as there is no evidence supporting its use in this condition, and established first-line therapies with proven safety profiles should be used instead. However, capsaicin may be considered as an adjunctive treatment specifically for cannabinoid hyperemesis syndrome (CHS), though the evidence remains mixed and of low quality.
For Hyperemesis Gravidarum (Pregnancy-Related)
First-line management should begin with non-pharmacologic interventions including dietary modifications (small, frequent bland meals, BRAT diet, high-protein/low-fat meals), ginger (250 mg capsule 4 times daily), and vitamin B6 (pyridoxine 10-25 mg every 8 hours) as recommended by the American College of Obstetricians and Gynecologists. 1
For persistent symptoms refractory to non-pharmacologic therapy, doxylamine is FDA-approved and recommended by ACOG as first-line pharmacologic treatment. 1 Doxylamine/pyridoxine combinations (10 mg/10 mg or 20 mg/20 mg) are safe, well-tolerated, and compatible with all trimesters and breastfeeding. 1
Second-line pharmacologic options include:
- H1-receptor antagonists: promethazine, dimenhydrinate, cyclizine 1
- Dopamine antagonists: metoclopramide, domperidone 1
- 5-HT3 antagonists: ondansetron (though this is typically reserved for more severe cases) 1
- Corticosteroids as third-line therapy 1
Capsaicin has no established role in hyperemesis gravidarum and should not be used. The evidence base for capsaicin is limited exclusively to cannabinoid hyperemesis syndrome, not pregnancy-related hyperemesis. 2, 3, 4, 5, 6
For Cannabinoid Hyperemesis Syndrome (CHS)
Topical capsaicin (0.1% cream applied to the anterior abdomen) may be considered as an adjunctive treatment for CHS, though evidence is mixed and of low methodological quality. 3, 6
Evidence for capsaicin in CHS:
The most recent systematic review (2024) found mixed evidence for capsaicin efficacy in reducing nausea and emesis in CHS patients presenting to the emergency department. 6 This review included 386 patients across five studies evaluating capsaicin cream.
The highest quality individual study was a double-blind randomized placebo-controlled trial (2020) that demonstrated:
- Mean nausea reduction at 60 minutes: 3.2 cm vs 6.4 cm on VAS (difference -3.2 cm, 95% CI -0.9 to -5.4 cm) 5
- 46% reduction in nausea from baseline with capsaicin vs 24.9% with placebo 5
- 29.4% of capsaicin patients achieved complete nausea resolution vs 0% with placebo 5
- However, no significant difference was detected at 30 minutes 5
A retrospective cohort study (2020) found that capsaicin did not significantly reduce ED length of stay (median difference 22 minutes, p=0.33), but did reduce total medications administered and opioid requirements (166.5 vs 69 mg OME). 4 Additionally, 67% of capsaicin visits required no further treatment prior to discharge. 4
Practical considerations for capsaicin in CHS:
Capsaicin has a favorable safety profile with minimal adverse events reported. 3, 4 The most common adverse effect is skin irritation at the application site, which led to treatment discontinuation in approximately 6% of patients. 5
The mechanism involves agonism of transient receptor potential vanilloid 1 (TRPV1) receptors, which may explain why CHS patients report symptom relief with hot showers. 2, 4
Capsaicin may be most useful as an over-the-counter adjunctive therapy that empowers at-home treatment, potentially decreasing unnecessary healthcare encounters. 4
Alternative Treatments for CHS
Dopamine antagonists (haloperidol, droperidol) show potentially more consistent benefit than capsaicin for CHS in the emergency department setting. 6 Both studies evaluating dopamine antagonists detected clinical benefit compared to usual care. 6
Standard antiemetic therapy with 5-HT3 antagonists (ondansetron) is often ineffective for CHS. 4
Critical Caveats
The evidence for capsaicin in CHS suffers from significant methodological limitations including small sample sizes, lack of standardization in treatment administration, and high risk of bias. 3, 6 All case reports and case series found capsaicin beneficial, but both retrospective cohort studies failed to demonstrate significant benefit on primary outcomes. 3
Capsaicin should never be used as monotherapy for severe hyperemesis requiring hospitalization—aggressive fluid resuscitation, electrolyte correction, and established antiemetics remain essential. 1
The most important intervention for CHS is marijuana abstinence counseling, as this addresses the underlying cause. 2