Related Clues:

• Cause of a rash reaction?
• Strong aversion, colloquially
• Poison ivy cousin
• Poison __
• Poison ivy family
• Abnormal reaction as to, say, pollen
• Unfavourable reaction to, say, pollen
• Unfavourable reaction as to pollen or some foods
• Hypersensitive reaction to certain substances
• Unfavourable reaction to pollen, certain foods etc
• Largely in an unfavourable reaction, maybe to pollen
• Unfavourable reaction as to certain foods
• Largely to do with adverse reaction
• Unfavourable reaction as to pollens or foods
• It's entirely this grey mixture that may make one 11 across