Racemethorphan

Racemethorphan is a cough suppressant and the racemic form of dextromethorphan. It is used in over-the-counter cough and cold preparations. Racemethorphan is a sigma-1 receptor agonist and an NMDA receptor antagonist. It is structurally similar to other morphinans such as codeine and morphine.

Pharmacology[edit | edit source]

Racemethorphan acts primarily as a sigma-1 receptor agonist and an NMDA receptor antagonist. The sigma-1 receptor is a chaperone protein at the endoplasmic reticulum (ER), and it modulates the activity of various ion channels and receptors. Meanwhile, the NMDA receptor is a glutamate receptor and ion channel protein found in nerve cells. By blocking this receptor, racemethorphan can prevent the cough reflex.

Medical Uses[edit | edit source]

Racemethorphan is used as a cough suppressant in many over-the-counter cold and flu medications. It is often combined with other ingredients such as antihistamines, decongestants, and pain relievers.

Side Effects[edit | edit source]

Common side effects of racemethorphan include drowsiness, dizziness, nausea, and vomiting. In rare cases, it can cause serious side effects such as hallucinations, severe dizziness, and trouble breathing.