Prune juice

Prune juice is made from dried plums, and the drying process can concentrate compounds that some people find reactive.

• Drying and concentration — when fruit is dried, its natural compounds (including any histamine-adjacent substances) become more concentrated than in fresh fruit, which may explain why dried fruits are more commonly reported as problematic

• Not well-studied — prune juice doesn't have a strong established mechanism in histamine intolerance literature, but reports of sensitivity to dried fruits are common enough to warrant moderate caution

Fresh plum juice, if available, would likely be a gentler alternative than prune juice.