High drug load pharmaceutical compositions and production methods thereof are provided. The pharmaceutical composition includes at least one viscous active pharmaceutical ingredient or a pharmaceutically acceptable salts thereof. The at least one viscous active pharmaceutical ingredient accounts for at least 60% by weight of the total solid weight of the pharmaceutical composition. The saturated solution of the at least one viscous active pharmaceutical ingredient has a viscosity of at least 20 centipoises at 25° C. Alternatively, the aqueous solution of the at least one viscous active pharmaceutical ingredient with a concentration lower than 55 wt % has at least a viscosity of at least 10 centipoises at 25° C.
