The food allergy, involves entities as diverse as cow's milk protein to peanut allergies as to legumes. The global prevalence of this entity has been increasing. In general, the medical doctor is the first to face these cases, therefore, should know very well their referral network to give an expeditious approach to each patient who visits him for a food allergy. We present the case of a 3-year-old infant who presented an urticarial reaction after the third ingestion of cooked lentils. He required corticosteroids and antihistamine management to reduce discomfort. The treatment indicated for food allergy to lentils is the exclusion of the diet, without knowing the temporality of this or its re-initiation, although several guides suggest attempting feedback at the age of 4 to 5 years.