Information about Thiomersal

Thiomersal uses

Thiomersal is used in preservation of the medicinal products.

How thiomersal works

Thiomersal belongs to the class of medications called as preservatives. It is used in minuscule quantity in some vaccines (e.g. tetanus and pertussis (DTP), diphtheria and tetanus toxoids (DT)) and works by preventing bacterial and fungal growth.

Common side effects of thiomersal

Irritation of ear, Allergic skin rash.

Available Medicine for Thiomersal

No medicine available

Expert advice for Thiomersal

  • Seek immediate medical attention in case of any severe allergic reactions. 
  • Tell your doctor if you are or planning to become pregnant or are breastfeeding.
  • Do not take if you are allergic to thiomersal or any of its ingredients.

Frequently asked questions for Thiomersal


Q. Is thimerosal safe and still used in vaccines?
Yes, thiomersal contains ethyl mercury and is considered safe with no studies indicating it as harmful. It is used in few multi-dose vaccines.

Content on this page was last updated on 16 February, 2017, by Dr. Varun Gupta (MD Pharmacology)