What do systematic reviews say?

Antihistamines vs placebo

Antihistamines may leads to lower nausea ‐ postoperative compared with placebo (low certainty).

• Interventions for preventing nausea and vomiting in women undergoing regional anaesthesia for caesarean section 2021 · Cochrane Headline outcomes only
  RR 0.44 [0.3, 0.64]
  4 studies · 514 participants
  Low