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Is Thimerosal halal?

Thimerosal is classified halal for halal use with High confidence. An ethylmercury-containing preservative used in some multi-dose vaccines and a few biological products. Synthetic; halal in itself. Single-dose pre-filled syringes are generally thimerosal-free.

Excipient (preservative) · Confidence: High

Also known as: thiomersal, ethylmercury

Looks Halal Ask pharmacist
What it is

An ethylmercury-containing preservative used in some multi-dose vaccines and a few biological products.

Source:FDA — Thimerosal and vaccinesCDC — Thimerosal in vaccines

Why it's here

Prevents bacterial contamination of multi-dose vials.

See:FDA — Thimerosal and vaccinesCDC — Thimerosal in vaccines

Why it may matter

Synthetic; halal in itself. Single-dose pre-filled syringes are generally thimerosal-free.

Source:FDA — Thimerosal and vaccinesCDC — Thimerosal in vaccines

Common sources
  • Synthetic

Questions to ask

  • Is a thimerosal-free, single-dose version available?

Reason codes

syntheticOrigin

Evidence & citations2

Audit

Common questions

Is Thimerosal halal?
RxHalal currently classifies Thimerosal as HALAL (High confidence). Synthetic; halal in itself. Single-dose pre-filled syringes are generally thimerosal-free. This is information only — not a fatwa or medical advice.
What is Thimerosal used for in medicines?
An ethylmercury-containing preservative used in some multi-dose vaccines and a few biological products. Prevents bacterial contamination of multi-dose vials.
What are common sources of Thimerosal?
Common sources include: Synthetic. Manufacturers often do not disclose which source is used.
Is a thimerosal-free, single-dose version available?
Ask your pharmacist or prescriber. RxHalal lists this because Thimerosal is halal in our cited database.