Background and Importance Epicutaneous Patch Tests (EPTs) are the first type of skin tests performed by Allergology Department to diagnose Type IV hypersensitivity allergic reactions (IVHAR) to drugs. They involve application of ointments for epicutaneous patches containing the active ingredient, prepared by the Pharmacy Department, followed by reading results 48 and 72 hours later. When there is suspicion of an IVHAR to hazardous drugs, compounding process must be adapted to protect the handler.

Aim and Objectives The aim of this study is to describe the design and formulation of EPT with Imatinib and Nilotinib, classified as Hazardous Drugs Group 1 by the National Institute for Occupational Safety and Health (NIOSH).

Material and Methods A request was made to the Pharmacy Department for an EPT for a patient suspected of IVHAR after treatment with Imatinib in order to confirm the diagnosis and consider switching to Nilotinib.

A literature search was conducted to determine the optimal concentration of both drugs within each EPT, as well as the best vehicle. A galenic control was established to evaluate the extensibility and organoleptic properties of the formula. The stability of the formula was determined in accordance with the risk matrix included in the Good Practices Guide for the preparation of medications in Hospital Pharmacy Services.

The handling of these drugs was always performed in a fume hood with HEPA-H14 filter, wearing a cap, glasses, FFP3 mask, gloves, disposable gown, and shoe covers.

Results Imatinib 5% petrolatum (pet.):

• Imatinib tablet 0.4 g

• Liquid pet. 2 g

• Petroleum Jelly q.s. 8 g

• Nilotinib 5% pet.:

• Nilotinib capsule 0.2 g

• Liquid pet. 1 g

• Petroleum Jelly q.s. 4 g

For the preparation of both ointments, the commercial pharmaceutical form was placed in a ZIP-type resealable bag with an ENFit connection. The active ingredients were pulverised using a specific roller-shaped device. Subsequently, liquid Vaseline was introduced using an ENFit syringe through the bag’s connection. After homogenisation, Vaseline filante was introduced in the same manner and homogenised again. Finally, it was dosed into individualised 1 mL ENFit syringes.

Conclusion and Relevance The preparation of EPT with hazardous drugs in the Hospital Pharmacy Department is totally feasible as long as the appropriate procedures and equipment are available.

Conflict of Interest No conflict of interest.