The purpose of this study is to determine if using preventive treatments such as Doxycycline (an anti-biotic) capsules, sunscreen with SPF 30, Hydrocortisone 1% cream and a moisturizer will help to reduce the incidence and severity of the skin rash associated with Cetuximab (Erbitux®) when compared to receiving standard care for the treatment of skin rash.

Of the 100 subjects who will participate in this study, 50 will be in the extensive treatment group and 50 will be in the standard care group. Subjects in the extensive treatment group will use Doxycycline capsule, 100 mg, taken twice daily, sunscreen SPF 30 or higher, moisturizer applied to the face, hands, feet, neck, back, and chest each morning after sunscreen, hydrocortisone 1% cream applied to the face, hands, feet, neck, back, and chest each evening.

Subjects will start taking the capsule and applying the creams three days prior to beginning cetuximab therapy. They will continue this regimen of taking the capsule and applying the creams for 8 weeks. If they develop severe skin rash as a result of cetuximab therapy, the study doctor may decide to reduce the amount of the dose of cetuximab that they receive or prescribe other medicines according to standard treatment recommendations, just as he/she would if the subject was not participating in this study. Subjects will be monitored at enrollment, 3 weeks into cetuximab treatment and at the end of cetuximab treatment for adherence, side effects and quality of life.

The standard care group will not receive preventive treatment, but they will be allowed to use sunscreen and moisturizer if desired. They, too, will be monitored at enrollment, 3 weeks into cetuximab treatment and at the end of cetuximab treatment for adherence, side effects and quality of life.

If a subject is assigned to this group and they develop a severe skin rash, the study doctor will treat their rash according to standard treatment recommendations, which may include Hydrocortisone 1% cream, Doxycycline capsules or other medications.

There will be a follow-Up period for both extensive treatment and standard care groups. At 6 months, 12 months, 18 months and 24 months, after the end of the subject's 8 week study treatment period, they will be contacted by telephone or discussed during their routine clinic visit.

Inclusion Criteria:

1. Age greater than or equal to 18 years
2. Diagnosis of colorectal or head and neck cancer
3. Receipt of at least one dose of cetuximab during the study time period

Exclusion Criteria:

1. Prior cetuximab treatment within the 6 months of study initiation
2. Current treatment with tyrosine kinase inhibitors
3. Patients who are pregnant or incarcerated