Nucleic acids are linear polymers (chains) of nucleotides. Each nucleotide consists of three components: a purine or pyrimidine nucleobase (sometimes termed nitrogenous base or simply base), a pentose sugar, and a phosphate group. The substructure consisting of a nucleobase plus sugar is termed a nucleoside.
Other studies of Remicade and methotrexate indicate that the two medications together can successfully reduce symptoms of psoriasis and psoriatic arthritis, the researchers report. Studies of Humira and Enbrel in conjunction with methotrexate also revealed the combination to be more effective than the biologic alone.
Methotrexate use has rarely caused serious (sometimes fatal) side effects, such as lung problems, lung infections (Pneumocystis jiroveci pneumonia), skin reactions, diarrhea, and mouth sores (ulcerative stomatitis). (See also Side Effects section.) Lumps (tumors/abnormal growths) may very rarely appear during methotrexate use.