Estimated Sulfur Dioxide Levels in Foods

≥100 ppm
  • Dried fruit (excluding dark raisins and prunes)
  • Lemon juice (non-frozen)
  • Lime juice (non-frozen)
  • Wine
  • Molasses
  • Sauerkraut juice
  • Grape juice (white, white sparkling, pink sparkling, red sparkling)
  • Pickled cocktail onions
50 to 99.9 ppm
  • Dried potatoes
  • Wine vinegar
  • Gravies, sauces
  • Fruit topping
  • Maraschino cherries
10.1 to 49.9ppm
  • Pectin
  • Shrimp (fresh)
  • Corn syrup
  • Sauerkraut
  • Pickled peppers
  • Pickles/relishes
  • Corn starch
  • Hominy
  • Frozen potatoes
  • Maple syrup
  • Imported jams and jellies
  • Fresh mushrooms
≤10 ppm
  • Malt vinegar
  • Canned potatoes
  • Beer
  • Dry soup mix
  • Soft drinks
  • Instant tea
  • Pizza dough (frozen)
  • Pie dough
  • Sugar (especially beet sugar)
  • Gelatin
  • Coconut
  • Fresh fruit salad
  • Domestic jams and jellies
  • Crackers
  • Cookies
  • Grapes
  • High fructose corn syrup
Note:
  • The FDA banned the use of sulfites from fresh fruits and vegetables other than potatoes
    • Packaged foods containing >10ppm residual SO2 equivalents must declare the presence of sulfites on the label
    • Sulfites may be listed on food package labels as sulfur dioxide, sodium or potassium bisulfite, sodium or potassium metabisulfite, sodium sulfite
  • Injectable epinephrine (EpiPen, TwinJect), injectable dexamethasone, isoprotenerol, and other drugs may contain sulfites




Diagnosis


Sulfite Challenge for Sulfite-exacerbated Asthma (Simon)

  • All doses should be swished for several seconds before swallowing
  • Measure FEV1 prior to dose and if symptoms develop
  • If the patient reacts to an active dose, then the challenge is stopped and deemed positive
Step 1 (placebo)
  • 10 mL vehicle solution (e.g. sulfite-free lemonade) then observe 30 min
Steps 2-4
  • Give 10 mL vehicle containing: 10, 50, and then 100 mg potassium metabisulfite; allow 30 min between doses
Step 5 (placebo)
  • 10 mL vehicle solution then observe 30 min
  • Simon: no skin testing unless a convincing history of anaphylaxis, and a capsule challenge (maximal 200 mg single dose) is done for patients with history of urticaria or anaphylaxis


Intensive Protocol(Bush)

Testing material: potassium metabisulfite
Step 1
SPT
0.001 mg/mL
0.01 mg/mL
0.1 mg/mL
1 mg/mL
Step 2
ID testing
0.02 mL of 0.001 mg/mL solution
Step 3
Oral challenge (solution, swish/swallow)
  • 1 mg, 10 mg, 25 mg, 50 mg, 100 mg
  • Interval 20 min
  • Spirometry pre/post each dose
Step 4
Oral challenge (capsule)
  • 1 mg, 10 mg, 25 mg, 50 mg, 100 mg
  • Interval 20 min
  • Spirometry pre/post each dose



Management

  • Avoidance of highly sulfited foods (>100 ppm) and drugs containing sulfite; very sensitive individuals may need to avoid foods containing >10 ppm (see table above)
    • Avoid all potato products in restaurants except baked potatoes with skins intact
    • Epinephrine should be used when necessary despite the fact that it may contain sulfite as a preservative
  • Unproven treatments include vitamin B12, atropine, doxepin, and cromolyn sodium


Epinephrine with Metabisulfites (Lieberman)

  • It is highly doubtful that the amount of metabisulfite contained in injectable epinephrine is sufficient to produce an adverse reaction even in a patient who has a history of a possible previous adverse reaction to metabisulfites.
  • A metabisulfite-free preparation of epinephrine may be available for ophthalmologic use, but there have been shortages
  • The following graded dose challenge approach (over 2-3 days to avoid issues due to pharmacologic effect of epinephrine) has allowed patients to take epinephrine preserved in metabisulfite:
    • 1:100,000 dilution
      • 0.1, 0.2, 0.4, 0.8 mL SC at 30 minute intervals
    • 1:10,000 dilution
      • 0.1, 0.2, 0.4, 0.8 mL SC at 30 minute intervals
    • 1:1000 (standard dilution for anaphylaxis)
      • 0.1 mL
      • If they have no problem with 0.1 mL (other than known effects of epinephrine), we deem it safe to take the 0.3 mL standard dose if they should need it


References