Lesson 18 Cough PDF - 3rd Medicine

Lesson 18 Cough 3° Medicine Professor: Vittoria Carrabs PhD Academic year: 2024/25  COUGH Is a useful and pshysiological mechanism important to clear the respiratory passages of foreign material and excess secretions. If smoker, encourage smoking cessation If taking angiotens...

Lesson 18 Cough 3° Medicine Professor: Vittoria Carrabs PhD Academic year: 2024/25  COUGH Is a useful and pshysiological mechanism important to clear the respiratory passages of foreign material and excess secretions. If smoker, encourage smoking cessation If taking angiotensin-converting enzyme (ACE) inhibitor, discontinue use (strong recommendation). MUCOLYTICS WET COUGH EXPECTORANTS DRY COUGH ANTITUSSIVE 1. ANTITUSSIVE MEDICATIONS: CODEINE Mechanism of action: Opioid drug (weak agonist) Symptomatic relief of dry cough Subanalgesic dose is adequate to suppress cough Bronchi sputum thickens, thus inhibiting ciliary activity Other opioids: MORPHINE AND METHADONE only used for palliative care in cases of lung cancer associated with distressing cough. ASRs: Drowsiness and constipation, urinary retention Respiratory depression is a risk with all centrally acting cough suppressants (opioids) Contraindicated in asthmatics and COPD! 1. ANTITUSSIVE MEDICATIONS: DEXTROMETORPHAN Mechanism of action: Opioid derivative that in our brain stem inhibits the “cough center” No sedative effects neither analgesia No respiratory depression. No addictive. ADRs: Confusion, excitation, nervousness, irritability and hallucinations. Abuse and recreational use reported. https://www.youtube.com/watch?v=aXOSp_lgqlI 1. ANTITUSSIVE MEDICATIONS: DEXTROMETORPHAN Temporary relief of coughs (antitussive, cough suppressant) caused by minor throat and bronchial irritation that may occur with common colds, allergies, or inhaled irritants. Also used fixed combination with other agents (e.g. paracetamol/phenylephrine pseudoephedrine/chlorfenamine). 2. MUCOLYTICS HOW TO FACILITATE MUCUS CLEARANCE ADEQUATE HYDRATION: Increase fluid intake orally or IV. REMOVE CAUSATIVE FACTORS: Smoking, pollution, allergens… 2. MUCOLYTICS Mechanism of action: breakdown of mucus structure, thus reducing it thickness Important in diseases in which there is an increased mucus production: Cystitic fibrosis COPD Respiratory infections Bacterial infection effects in the bronchi Hypersecretion of mucus Increased thicknes of the mucus Inhibition of ciliar transport 2. MUCOLYTICS ACETYLCYSTEINE Mechanim of action: liquefies mucus by reducing disulfide bonds in mucus proteins Adjunctive treatment for patients with altered mucous secretions associated with conditions such as: acute and chronic bronchopulmonary disorders, pulmonary complications of cystic fibrosis; pulmonary complications of thoracic and cardiovascular surgery Used during anesthesia and in the preparation for diagnostic bronchial studies. 2. MUCOLYTICS ACETYLCYSTEINE ANTIDOTE in paracetamol overdose: How acetylcysteine works as an antidote for paracetamol (acetaminophen) overdose? Paracetamol is primarily metabolized in the liver through glucuronidation and sulfation. A small portion is converted into a toxic metabolite, NAPQI (NAPQI levels increase significantly) Glutathione, which normally neutralizes NAPQI, gets depleted. Excess NAPQI binds to liver cells, causing cell death (necrosis) and potentially leading to acute liver failure. Acetylcysteine: 1. Restores glutathione by providing precursors (cysteine) for its synthesis. 2. Acts as a direct antioxidant, reducing oxidative damage. Timing:Most effective if administered within 8-10 hours of overdose 2. MUCOLYTICS HAZARD OF MUCOLYTICS!!!!!! They destroy elasticity of the mucus while reducing viscosity. Elasticty is necessary for mucociliary transport. Patient must be able to cough adequately to remove the mucus. Not for patients who don´t cough adequately or in combination with antitusive (elderly patients and babies)  3. EXPECTORANTS Mechanism of action: Stimulate mechanism for expulsion of mucus from respiratory tract decrease its viscosity and facilitates its removal Smoking increases mucus production and its viscosity Not recommended if patient has neuromuscular impairment AMBROXOL Increase volume and decrease viscosity of mucus Stimulates synthesis and release of surfactant by type II pneumocytes. Surfactant: antiglue factor reduces adhesion of mucus to the bronchial wall. The anti-inflammatory properties of ambroxol lead to a decrease in redness of the throat and thus ambroxol relieves pain in acute sore throats with a rapid onset of action and a long duration of effect (3 hours). 3. EXPECTORANTS GUAIFENESIN Orally administered Symptomatic management of productive cough to loosen and thin sputum and bronchial secretions and ease expectoration. Used in fixed combination with other agents (e.g., acetaminophen, chlorpheniramine, dextromethorphan, ephedrine, phenylephrine, pseudoephedrine) for the temporary relief of productive cough and/or other symptoms (nasal congestion, fever). 4. SURFACTANTS BERACTANT, PORACTANT ALPHA They are effective in the prophylaxis and management of respiratory distress syndrome in newborn babies (especially premature babies in whom endogenous surfactant production is deficient) Derivatives of the physiological pulmonary surfactant They are administered directly into the tracheobronchial tree via an endotracheal tube 4. OTHER TREATMENTS GABAPENTIN Antiepileptic. May improve cough-related quality of life in older adults with refractory chronic cough Tonsillectomy reported to reduce cough in patients with chronic cough and enlarged tonsils 5. CYSTIC FIBROSIS TREATMENT Pulmonary disease characterized by thickening of mucus secretions with impaired clearance of the airways and progressive lung damage. mucolytic = breaks down mucus DORNASE ALFA Mucolytic enzyme similar to natural DNAse, that reduces the viscosity of sputum by degradating extracelular DNA It is indicated to improve the lung function of patients with cystic fibrosis In this disease, thick secretions that are high in DNA build up, leading to blockages in the airways and increasing the risk of chronic respiratory infections.