Introduction: Prevalence of peristomal dermatoses ranges between 6-80%1 and more commonly affects patients with urostomies and ileos- tomies, than with colostomies. Most common causes include irritant con- tact dermatitis from urine/faeces, mechanical dermatitis, chronic papillo- matous dermatitis, seborrheic dermatitis and allergic contact dermatitis. We report an unusual case of allergic contact dermatitis to printing ink on stoma bag which has not knowingly been reported before. Case description: A 66-year-old male, presented with a pruritic rash under colostomy bag, not responding to topical emollients and steroids. Examination findings were of an eczematous rash with no obvious leak at stoma site or from bag. He was not on any medication such as Nicorandil which might be contributing to peristomal dermatitis/ulceration. Provi- sional diagnoses were allergic contact dermatitis and irritant contact dermatitis. First patch test for standard european battery was negative. Histopathology had shown eczematoid spongiotic dermatitis, consistent with allergic/irritant contact dermatitis. He was treated with several emollients, topical Trimovates, Betnovates and topical 0.1%Tacrolimus; however, it had made no significant difference even by occlusion with hydrocolloid dressing.