There are 240 milligrams of pseudoephedrine contained within a Sudafed 24 Hour pill, according to Sudafed. Pseudoephedrine is a decongestant and is the primary active ingredient in a Sudafed 24 Hour pill.
Other inactive ingredients in a Sudafed 24 Hour pill include cellulose triacetate, iron oxide, hypromellose and magnesium stearate. Sudafed 24 Hour is designed to provide temporary relief for nasal congestion due to the common cold, hay fever or other upper respiratory allergies. Adults and children 12 years and older are directed to not exceed one tablet in 24 hours. Children under 12 years of age should not use Sudafed 24 Hour.