DEGORAN L

Chlorphenamine is a potent antihistamine (H₁-antagonist). Antihistamines diminish or abolish the actions of histamine in the body by competitive reversible blockade of histamine H₁-receptor sites on tissues. Chlorphenamine also has anticholinergic activity.

Dextromethorphan is a non-opioid antitussive drug. The major metabolite of dextromethorphan, dextrorphan, binds with high affinity to σ-receptors to produce its antitussive activity without exhibiting the classic opiate effects that occur from binding into μ- and δ-receptors. In larger than therapeutic doses, dextrorphan is also an antagonist of N-methyl-D-aspartate (NMDA) receptors.

Paracetamol is a medication used to treat pain and fever. It does appear to selectively inhibit COX activities in the brain, which may contribute to its ability to treat fever and pain.

Phenylpropanolamine is a sympathomimetic agent which is used as a decongestant and appetite suppressant. It was commonly used in prescription and over-the-counter cough and cold preparations. Although originally thought to act as a direct agonist of adrenergic receptors, phenylpropanolamine was subsequently found to show only weak or negligible affinity for these receptors, and has been instead characterized as an indirect sympathomimetic which acts by inducing norepinephrine release and thereby activating adrenergic receptors.