Tromethamine

A blood acid reducer that is used to stabilize people with heart attacks.

Pfizer changed their formulation for 5-11-year-old kids. They added tromethamine.

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Side effects include:

Adverse effects may include respiratory depression, local irritation, tissue inflammation, injection site infection, febrile response, chemical phlebitis, venospasm, hypervolemia, IV thrombosis, extravasation (with possible necrosis and sloughing of tissues), transient decreases in blood glucose concentrations, hypoglycemia, and hepatocellular necrosis with infusion via low-lying umbilical venous catheters.