Ketoconazole in Treating Participants With Ongoing EGFR Inhibitor-Induced Rash

Inclusion Criteria: * Patient has developed a rash or symptoms of a rash (cutaneous burning) characteristic of an EGFR inhibitor (health-care provider report of the rash with no other documentation is permitted) * Patient is anticipated to continue for at least 28 days with an EGFR inhibitor or restart =\< 14 days of registration and continue for at least 28 days * Mayo only: Patient is willing to provide a skin biopsy for correlative research; Note: Can be waived with permission of study chair (documentation such as an email must be provided) * Patient must complete baseline quality of life (QOL) packet Exclusion Criteria: * Patient has a prior allergy or intolerance of ketoconazole * Patient has an allergy or intolerance to sulfites