If a patch test turns up a reaction to “Black-Rubber Mix,” which includes paraphenylenediamine, consider whether the patient has exposure to the rubber in tires. Car mechanics may be affected by this allergy, Dr. Perryman said.
Neomycin: A drop of trouble
Allergy to the antibiotic neomycin can be triggered by exposure to gentamicin and tobramycin eye drops. Patients may believe they have an infection, Dr. Perryman said, so consider getting a culture. In some cases, an allergic reaction to neomycin may be incorrectly diagnosed as cellulitis.
Nickel: Not just a jewelry hazard
Jewelry and coins can trigger nickel allergies, but be aware that systemic nickel allergy can also trigger skin problems from a patient’s diet. It may be necessary to put patients on a low-nickel diet that avoids foods such as healthy grains, greens (especially spinach), nuts, legumes, and chocolate. “I always feel bad” putting patients on a restrictive diet, Dr. Perryman said, but it can be helpful to take 500 mg of vitamin C three times a day since it binds to nickel.
Cobalt: Watch the chocolate and coffee
Jewelry with cobalt can cause an allergic reaction. Dr. Perryman tells patients to buy an inexpensive “spot test” product online that detects whether jewelry has nickel or cobalt. Cobalt allergy can also trigger symptoms in patients exposed to “hard metal” industrial tools, cement, and masonry. Workers in the plastics and dye industries may be exposed too.
Like nickel, Dr. Perryman said, systemic cobalt allergy related to diet is also possible. The list of foods that contain higher levels of cobalt is long, and includes apricots, beans, beer, chocolate, coffee, nuts, tea, and whole-grain flour.
Dr. Perryman also mentioned several other allergens to keep in mind:
- Chromate can trigger reactions in people who wear leather shoes (the metal can be used in tanning). It can also cause problems in workers exposed to it via cement, bricks, drywall, and metal plating.
- Chromium picolinate, an over-the-counter supplement, can cause systemic dermatitis.
- Gold in jewelry can trigger an allergic reaction. Talk to patients about replating their jewelry, Dr. Perryman said.
- Rubber can trigger reactions due to exposure to rubber bands, makeup sponges, and rubber gloves (even nitrile ones). Be aware that both rubber and latex allergies may coexist and consider a blood test for latex allergy.
- Systemic balsam allergy related to an individual’s diet is possible. Tomato is an especially big villain on this front, along with citrus fruits, spices, cola, chili, and chocolate.
Dr. Perryman disclosed consulting work for IntraDerm. SDEF and this news organization are owned by the same parent company.