Delsym is an American brand-name over-the-counter cough syrup developed and marketed by the pharmaceutical company, Reckitt Benckiser. The active ingredient in Delsym is dextromethorphan hydrobromide, an anti-cough agent approved by the FDA in 1982 34. The official Delsym site notes that its product is formulated as either orange or grape flavored time-released syrup available in 3-ounce and 5-ounce bottles. In addition to the active ingredient of dextromethorphan, Delsym also contains numerous inactive ingredients 34.

Dextromethorphan Hydrobromide

Dextromethorphan is an opioid typed analgesic and anti-trussive agent used to relieve coughs due to colds or flu, but not chronic coughs that occur with smoking, asthma or emphysema 34. Dextromethorphan relieves cough by suppressing the cough reflex in the brain 34. Within Delsym syrup, dextromethorphan is surrounded by edible plastic called polistirex, which takes time to dissolve in the stomach, thus allowing for the claim, 12-hour time-released formula 34. Five milliliters of dextromethorphan polistirex is equivalent to 30 milligrams dextromethorphan HBr 34.


Delsym contains five ingredients that can generally be called binders: ethyl cellulose, propylene glycol, polyethylene glycol 3350, edetate disodium, sucrose and high-fructose corn syrup. Binders keep all the ingredients intact. Binders are usually starches, sugars, cellulose or modified cellulose. Polyethylene glycol 3350 bonds to water in the gut and can also function as an osmotic laxative, notes the Dictionary of Pharmaceutical Medicine 1.

Emulsifiers and Stabilizers

Delsym also contains tragacanth, which absorbs water and is used in pharmaceutical syrups as an emulsifier, thickener and stabilizer. Also present is xanthan gum, which is capable of producing a large increase in the viscosity of a liquid, making it thicker, as does high-fructose corn syrup. Another ingredient is polysorbate 80, which is a stable and nontoxic surfactant used as a detergent and emulsifier in many pharmacological applications. Vegetable oil is another common emulsifier present in Delsym.


Delsym also contains propylparaben and methylparaben, which are in a group of chemicals widely used as preservatives in the pharmaceutical industry because of their bactericidal and fungicidal properties. Citric acid anhydrous is another inactive ingredient that functions as a natural preservative and can retard the growth of molds, yeasts and some bacteria.

Coloring and Flavoring

As noted above, Delsym cough syrup is offered in two flavors: the grape variety contains its own flavors; in addition to Red #33 and Blue #1 dyes; the orange variety contains its own flavors in addition to Yellow #6 dye. Both varieties contain purified water, whereas the sucrose and high-fructose corn syrup would add to the syrup's sweetness.