Causes of Mouth Sores
Chemotherapy kills cancer by interfering with the growth of rapidly
dividing cells. Unfortunately, the mucous linings of the mouth are
comprised of rapidly dividing cells, so chemotherapy can cause mouth
The following chemotherapy drugs will cause mouth sores in more than
one third of cancer patients:
Actinomycin (Cosmegen), Busulfan (Myleran, Busulfex), Cytarabine
(Cytosar-U), Daunorubicin (Cerubidine), Docetaxel (Taxotere),
Doxorubicin (Adriamycin, Rubex), Epirubicin (Ellence), Floxuridine
(FUDR), Fluorouracil (5-FU, Adrucil, Carac, Efudex, Fluoroplex),
Idarubicin (Idamycin, Idamycin PFS), Isotretinoin (Accutane),
Liposomal doxorubicin (Doxil), Methotrexate (Rheumatrex, Trexall),
Mitomycin (Mutamycin), Mitoxantrone (Novantrone), Mechlorethamine
(Mustargen), Oprevelkin (Neumega), Paclitaxel (Taxol, Onxal),
Pemetrexed (Alimta), Plicamycin (Mithracin), Procarbazine (Matulane),
Teniposide (Vumon), Trimetrexate (Neutrexin, TMQ, TMTX), Tretinoin
Mouth sores are less common with the following chemotherapy drugs, but
still occur in at least 10% of cancer patients:
Alemtuzumab (Campath), Asparaginase (Elspar, Kidrolase), Bleomycin
(Blenoxane), Capecitabine (Xeloda), Carboplatin (Paraplatin),
Cyclophosphamide (Cytoxan, Neosar), Etoposide (VePesid, Toposar,
Etopophos), Gemcitabine (Gemzar), Gemtuzumab ozogamicin (Mylotarg),
Hydroxyurea (Hydrea), Interleukin 2 (Proleukin), Irinotecan
(Camptosar), Liposomal daunorubicin (DaunoXome), Lomustine (CeeNU),
Melphalan (Alkeran), Oxaliplatin (Eloxatin), Pentostatin (Nipent),
Rasburicase (Elitek), Thiotepa (Thioplex), Topotecan (Hycamtin),
Trastuzumab (Herceptin), Tretinoin (Vesanoid), Vinblastine (Velban,
Alkaban AQ), Vincristine (Oncovin, Vincasar PFS).
Mouth sores can also occur with radiation therapy, especially
radiation therapy for head and neck cancer. High dose chemotherapy is
more likely to cause mouth sores, as is chemotherapy that is given on
a daily protocol as opposed to weekly.
Preventing Mouth Sores
Before you start chemotherapy, have a check-up and general cleaning at your dentist.
Sucking on ice chips while receiving the chemotherapy infusion may
help prevent mouth sores. The cold reduces blood flow to the mouth,
decreasing the likelihood of your getting mouth sores.
Drink plenty of water, as this will help prevent your mouth from
Sucking on hard candy such as lemon drops or Creamsavers can also help
by promoting saliva production. (Note that some sugar-free candy
contains sorbitol, which can cause diarrhea, so check the ingredients
before using sugar-free hard candy.)
A new drug, Kepivance (keratinocyte growth factor, palifermin), helps
stimulate the growth of the lining of the mouth. It is currently
undergoing clinical trials to determine whether it helps prevent mouth
sores in cancer patients.
Here are a few helpful hints for
dealing with the discomfort.
- Avoid eating hot, salty, acidic (e.g., orange juice,
grapefruit, lemon, lime and other
citrus, tomato, V-8 juice, pickles), sour or spicy food and beverages. Drink apple juice,
gatorade/pedialyte, and water instead. Avoid alcohol and
caffeine (coffee, caffeinated tea, caffeinated soda). (Note that many liquid cough medicines contain alcohol.)
Food should be lukewarm, soft and
bland (e.g., spaghetti/macaroni, jello, applesauce, bananas,
milkshakes, yogurt, cottage cheese, baby food, oatmeal,
pudding, soup, scrambled eggs, mashed potatoes). Avoid hard and rough foods like
chips, crackers, granola, nuts and pretzels.
- Try liquid supplements such as Ensure, Glucerna, Boost, and Carnation
- Let soda sit overnight to reduce the amount of carbonation and
stir it before drinking. (Coca
Cola tastes pretty bad warm and without fizz, but Dr. Pepper, Sierra Mist, and
Ginger Ale actually taste pretty good.)
- Eat popsicles, sherbet, ice cream, frozen yogurt and other chilled
foods. (Note, however, that milk products may be more difficult to
digest and so should be avoided if you are suffering from nausea and
vomiting. On the other hand, Breyer's Mint Chocolate Chip Ice Cream
and Breyer's Mint Oreo Ice Cream were among the few foods I could keep
down during chemotherapy. The mint masked the metallic taste
of the chemo and vomit.)
- Drink liquids with a straw.
- Eat food with a teaspoon instead of a tablespoon.
- Use petroleum jelly, Vaseline, Chapstick or Blistex on your lips.
- Don't smoke or use chewing tobacco.
- Capsaicin Taffy may provide
- Your doctor might prescribe a topical anesthetic such as
lidocaine, xylocaine, Ambesol or Orajel. But be careful, as some anesthetics may interfere with
your ability to swallow and the gag reflex. This can cause choking if
taken before eating.
- Avoid topical steroids, as they can increase your risk of infection.
- Coat the blisters with a mixture of Maalox (or Mylanta or
Milk of Magnesia or Sucralfate or Kaopectate)
and Benadryl. This can also be used as a mouth rinse. (Your doctor can
also prescribe a mixture of Maalox, Benadryl and Viscous Lidocaine. Your
doctor might prescribe a mouth rinse such as nystatin, PerioGard or
Peridex. Note that Peridex may stain your teeth and tastes
horrible. Sucralfate and Kaopectate also taste horrible.)
You should check with your doctor before using this, especially if you
are suffering from diarrhea, vomiting or constipation.
- Betadine mouthwash diluted with water (half and half) may help,
but it may stain your teeth. Do not use if you are allergic to iodine.
Brushing your teeth helps prevent the problem from getting
worse, but can also cause further pain.
- Use a soft-bristle toothbrush when brushing your teeth. You can
also substitute a foam toothbrush, cotton swab (Q-tip) or gauze. Do not use an electric
toothbrush or floss.
- Substitute a paste of baking soda and water instead of tooth paste.
- Do not use Listerine or other store-bought mouthwash, as they
contain alcohol and will
irritate your mouth (burning sensation). Instead of mouthwash, rinse or gargle with a mix
of 1 teaspoon baking soda in a cup or two of water, perhaps with a
pinch or two of salt added. Your dentist may be able to suggest an
- A saline mouthwash or artificial saliva can help.
Copyright © 2005-2018 by Mark Kantrowitz. All rights reserved.
Suggestions and corrections are welcome and should be sent to