Aims: There is substantial interest in ginger as an adjuvant therapy for chemotherapy-induced nausea and vomiting (CINV). However, an up-to-date evidence synthesis to guide optimal dosing regimen is lacking, which hinders translation into practice. This study aimed to synthesise the evidence on the effect of ginger on CINV compared to placebo or usual care.
Methods: This systematic review and meta-analysis evaluated the safety, effect, and optimal dosing regimen of oral ginger supplementation on CINV in people of any age. Five databases were searched from inception to September 2023 for controlled trials. Quality of evidence was appraised with Cochrane RoB2 and GRADE. Data were pooled using Revman.
Results: N=29 studies were included (8% of participants were children; 83% of studies administered ginger in capsule form). In adults, ginger supplementation of any dose, duration, and frequency reduced the likelihood of acute nausea incidence by 40% (OR: 0.6; 95%CI: 0.41, 0.80; GRADE: Moderate) and delayed nausea incidence by 30% (OR: 0.7; 95%CI: 0.52, 0.97; GRADE: Moderate). Examination of dosing regimens found that administration of ginger 3-4 times daily and intervention duration >3 days were beneficial for nausea incidence. In adults, ginger of any dosing regimen reduced likelihood of acute vomiting by 60% (95%CI: 0.25, 0.71; GRADE: Low) and number of acute (SMD: -0.6; 95%CI: -0.89, -0.22; GRADE: Moderate) and delayed vomiting episodes (SMD: -1.0; 95%CI: -1.55, -0.36; GRADE: Very low). Ginger had no effect on anticipatory nausea incidence, acute nor delayed nausea severity, nor any adverse event. Data were unable to be pooled for studies on children.
Conclusions: Administration of ginger 3-4 times daily and for >3 days might be favourable for CINV in adults, but optimal ginger dose remains inconclusive, and evidence is scarce in children.