The present invention relates to compounds, compositions, and methods useful for modulating the expression of genes associated with respiratory and pulmonary disease, such as cholinergic muscarinic receptor genes, using short interfering nucleic acid (siNA) molecules. This invention also relates to compounds, compositions, and methods useful for modulating the expression and activity of cholinergic muscarinic receptor genes, or other genes involved in pathways of cholinergic muscarinic receptor gene expression and/or activity by RNA interference (RNAi) using small nucleic acid molecules. In particular, the instant invention features small nucleic acid molecules, such as short interfering nucleic acid (siNA), short interfering RNA (siRNA), double-stranded RNA (dsRNA), micro-RNA (miRNA), and short hairpin RNA (shRNA) molecules and methods used to modulate the expression of M3 muscarinic acetylcholine receptor or cholinergic receptor muscarinic 3 (CHRM3).