It will be developed and evaluated the antihistamine potential of a gel containing alpha-bisabolol. Method: Interventional and cross-sectional study, with convenience sampling, conducted with 20 volunteers. The forearm will be sensitized at four points (A, B, C and D). Point A: positive control will be sensitized with a drop of histamine at a concentration of 10 mg / Ml. Point B: histamine will apply and immediately after, the alpha bisabolol gel with a concentration of 0.5%. Point C: histamine and gel with 2.5% alpha-bisabolol will apply. Point D will be sensitized with a drop of histamine and 5.0% alpha-bisabolol gel. The test reading at each point will occur 15 minutes after the procedure. For the analysis of the results, the T Test will be applied.

Context:. Phytotherapy has been widely used to treat health with a prophylactic, curative and palliative purpose due to its easy access and low cost when compared to other available drug forms. Some plant species have antiallergic and anti-inflammatory properties that can be used to help contain signs and damage in allergic reactions, triggered mainly by histamine such as: pain, redness, heat and edema. Alpha-bisabolol, extracted from Candeia, has several applications in the treatment of illnesses, however, there are no studies on the therapeutic potential for antihistamine. Objective: To develop and evaluate the antihistamine potential of a gel containing alpha-bisabolol. Method: Pilot study, interventional, cross-sectional study, with convenience sampling, conducted with 20 volunteers. The forearm will be sensitized at four points (A, B, C and D). Point A: positive control sensitized with a drop of histamine at a concentration of 10 mg / Ml. Point B: histamine will be applied and immediately after, the alpha bisabolol gel with a concentration of 0.5%. Point C: histamine and gel with 2.5% alpha-bisabolol will be applied. Point D will be sensitized with a drop of histamine and 5.0% alpha-bisabolol gel. The test reading at each point will occur 15 minutes after the procedure. For the analysis of the results, the T Test will be applied.

Inclusion Criteria:

• participants without allergy-related diseases, non-pregnant women and who agreed to cooperate in carrying out the research by signing the consent form aged between 18 and 60 years of both sexes.

Exclusion Criteria:

• participants who had a history of previous anaphylaxis, extensive dermatitis, use of antihistamines, colds or steroids.
• participants who had a negative reaction to histamine and/or withdrew their consent at any stage of the study.