Some people (less than 2 or 3 %) develop some allergic reaction to E-Juice due to VG or PG.
If you are concerned about it, please contact a physician.
Propylene Glycol (Abbreviated as PG)
An ingredient found in many brands of E-Juice. Some users have reported an allergic reaction to it and must therefore use 100% VG Juice instead. This is one of the ingredients used that when heated will produce vapor that can be inhaled. Typically, PG produces less vapor than its VG counterpart but provides more throat hit. PG has been used medically for many years in asthma inhalers.
Vegetable Glycerol or Vegetable Glycerin (Abbreviated as VG)
An ingredient found in most brands of E-Juice. This is one of the ingredients used that when heated will produce vapor that can be inhaled. Typically, VG produces more vapor than its PG counterpart but provides less throat hit. Some users who are allergic to PG must use 100% VG Juices.