1 A physical change, such as a state change or dissolving, does not create a new substance, but a chemical change does. 2  In a chemical reaction, the atoms and molecules that interact with each other are called reactants. 3  In a chemical reaction, the atoms and molecules produced by the reaction are called products. In a chemical reaction, the atoms and molecules produced by the reaction are called products. 2  In a chemical reaction, only the atoms present in the reactants can end up in the products. 3  No new atoms are created, and no atoms are destroyed.
Humira (adalimumab) is a biologic drug that works by blocking a protein known as TNF-alpha. Normally, TNF-alpha helps fight infection, but in excess amounts, it can cause painful inflammation and severe joint damage -- common symptoms of rheumatoid arthritis and other forms of inflammatory arthritis.
The most common adverse reaction with Humira was injection site reactions. In placebo-controlled trials, 20% of patients treated with Humira developed injection site reactions (erythema and/or itching, hemorrhage, pain or swelling), compared to 14% of patients receiving placebo.