A eutectic-based self-nanoemulsified drug delivery system (SNEDDS) is formulated from polyoxyl 35 castor oil (Cremophor), medium chain mono- and diglycerides (capmul), essential oils, and a pharmacologically effective drug or nutraceutical or dietary supplement. The preferred pharmacologically effective drug is a poorly water soluble drug, such as ubiquinone (CoQ.sub.10). The SNEDDS can be further incorporated into a powder to produce a solid dosage form. The solid dosage form contains the SNEDDS, a copolymer of vinylpyrrolidone and vinyl acetate (Kollidon VA 64), maltodextrin, and microcrystalline cellulose (MCC).