August 09, 2011
Image of Thimerosal 3D Image of Thimerosal

Thimerosal is the generic name for a mercury-based topical antiseptic and antifungal agent that came to be far better known by the Eli Lilly trade name Merthiolate. Outside the United States, its generic name is thiomersal. It has also been used as a vaccine preservative, but this use is being phased out in many countries. M. S. Kharasch at the University of Maryland patented thimerosal and similar compounds in 1928.

MOTW update:
August 10, 2020

Thimerosal is a mercury-based topical antiseptic and antifungal agent that is sold under the trade name Merthiolate. It is also used as a vaccine preservative. Timerosal is claimed to be an inert ingredient in medications, but a recent study performed at the University of California, San Francisco, and the Novartis Institutes for BioMedical Research showed that it reaches blood levels in rats that may interact with biological targets. This finding doesn’t necessarily imply toxicity but it might be sufficient to prompt drug manufacturers to revisit vaccine formulations.

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