Log in
Pharmacology · Drugs and Prescriptions

Prenoxdiazine

Prenoxdiazine (Libexin)

Prenoxdiazine is a peripherally acting antitussive agent, an oxadiazole derivative. The drug effectively suppresses the cough reflex without having a depressing effect on the central nervous system.

Test your knowledge on this topicAsk the AI
Pharmacological groupAgents acting on the respiratory system; peripheral antitussives.
Chemical structureOxadiazole derivative.
Presentation0.1 g tablets.
Duration of action3–4 hours.
How to write a prescription
Rp.: Tab. "Libexin" 0,1
D.t.d. N 20
S. Внутрь по 1-2 таблетки 2-4 раза в день, не разжевывая

Alternative notations: Tab. Libexini 0,1; Tab. Prenoxdiazini 0,1; Tabulettas "Libexin" 0,1

Dosage form
Tab. 0.1 g
Administration
Orally, 0.1–0.2 g 2–4 times a day
Group
Agents acting on the respiratory system
2 min readFor medical studentsUpdated 09/24/2026
Material prepared by WhiteCoat Pro editorial team based on platform study guidesReviewed by medical editor: Aulov A. A., general practitioner · 09/24/2026

Mechanism of action

Prenoxdiazine exerts its effect at the peripheral level by acting directly on the sensory receptors of the bronchial mucosa. The main components of the mechanism include:

  1. Local anesthetic effect: reduction of receptor sensitivity, which prevents the initiation of the cough reflex.
  2. Bronchodilator effect: relaxation of the bronchial smooth muscle, facilitating breathing.
  3. Anti-inflammatory effect: suppression of inflammatory processes in the respiratory tract.

Pharmacological effects

Unlike centrally acting antitussives (e.g., codeine), prenoxdiazine does not affect the cough center in the brain. This eliminates the risk of drug dependence and respiratory center depression, making it the drug of choice when cough suppression without a sedative effect is required.

Test your knowledge on the topicTasks from the «Pharmacology» course bank — instant answers and explanations.

Side effects

The most common adverse reactions include:

  • Numbness of the tongue (associated with the local anesthetic effect of the drug).
  • Dry mouth.
  • Gastrointestinal disorders (diarrhea).

Prescription details

The drug is taken orally. The standard therapeutic dosage is 0.1–0.2 g per dose, with a frequency of 2–4 times a day. It is important to consider that the drug does not have an expectorant effect, so it should not be combined with mucolytics without clinical indications.

How to memorize

Libexin — "liberates" (frees) from cough peripherally, without affecting the brain (unlike opioids).

Class and exam questions

What is the main difference between prenoxdiazine and codeine?

Prenoxdiazine acts on peripheral receptors and does not affect the central nervous system, whereas codeine is a centrally acting narcotic agent with a risk of dependence.

Why might numbness of the tongue occur when taking prenoxdiazine?

This is a consequence of its local anesthetic effect, which also ensures the suppression of the cough reflex in the bronchi.

Is prenoxdiazine classified as a mucolytic?

No, prenoxdiazine is a peripherally acting antitussive agent. Mucolytics (e.g., ambroxol) have a different mechanism of action and are aimed at liquefying sputum.

Something unclear? Ask the AIThe AI tutor has read the material on "Prenoxdiazine" and will explain it in simple terms.

What else to study on this topic

  • Comparative characteristics of centrally and peripherally acting antitussives.
  • Differential diagnosis of cough: when antitussives are indicated versus expectorants.
  • Risks of using opioid antitussives (codeine) and their regulation.
  • The role of the bronchodilator component in cough therapy.
  • Classification of agents affecting the respiratory system as a whole.

Master the entire topic in the «Pharmacology» course

This is a summary. The course covers everything tested in classes and exams.

  • Complete study guide on "Prenoxdiazine" and another 5,304 pages of the subject
  • Assignments and quizzes after every topic — just like in a colloquium
  • AI tutor answers questions on the topic anytime
  • 116 video lessons on the subject
Open full reviewSubject curriculumfrom 599 ₽ per month

Other topics in the «Drugs and Prescriptions» section

Atropine sulfateAceclidineAeronHexoprenalinePirenzepineIpratropium bromideXylometazolineMetocinium iodideNaphazolineNeostigmineNorepinephrinePipecuronium bromidePlatyphyllineSalmeterolSuxamethoniumTropicamideFenoterolEpinephrineEphedrine hydrochlorideAcetaminophenBromocriptineSodium valproateDiazepamZolpidem
The entire "Drugs and Prescription" section

Free video lessons: pharmacologyShort lessons with study notes — no registration required.

Watch lessons

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.