202 1 knowledge of medicine and health pharmacy: drugs for treating cough

Cough is a common symptom in life and clinic. In life, if you eat a Chongqing hot pot, you will cough when you choke; Old people who smoke for more than ten years will cough when they smoke; In winter, the smog is serious and the dust particles are filled, so people will cough when they travel. Clinically, a cold may be accompanied by cough; Some infectious diseases such as pneumonia and tuberculosis can also cause cough; The side effect caused by taking some drugs is also cough ... So do we need to use drugs for cough, and what drugs do we need?

First, an overview of cough

Cough is a common symptom of respiratory tract, which is caused by inflammation, foreign body, physical or chemical stimulation of trachea, bronchial mucosa or pleura. Cough is a protective reflex activity, which can discharge mucus and foreign bodies in the respiratory tract and keep the respiratory tract clean and unobstructed. Therefore, it can be said that coughing is a beneficial action, sometimes seen in healthy people. Under normal circumstances, for mild and infrequent cough, as long as sputum or foreign bodies are discharged, the cough will be relieved naturally, and antitussive drugs are not needed; If there is too much phlegm, simply using antitussive drugs will make phlegm stay in the airway, which is harmful and useless. Therefore, antitussive drugs should be used when coughing frequently and violently without phlegm or less phlegm.

Second, the classification of cough

(1) A cough without phlegm or with little phlegm is called a dry cough. Dry cough or irritating cough is common in acute and chronic pharyngolaryngitis, laryngeal cancer, bronchial foreign bodies, bronchial tumors and pleural diseases. Cough with expectoration is called wet cough, which is common in chronic bronchitis, pneumonia, lung abscess and cavitary pulmonary tuberculosis.

(2) Cough with cold: mostly mild or dry cough, sometimes a small amount of thin white sputum can be seen. Cough after influenza may be accompanied by chest pain, high fever, headache and sore throat.

(3) Pertussis: It mostly occurs in children and is paroxysmal spastic cough. When spastic cough is terminated, it is accompanied by cock-like inspiratory echo, and the course of disease lasts for 2-3 months.

(4) Cough with bronchial lesions: Before the onset of bronchial asthma, symptoms such as nasal congestion, runny nose, sneezing and chest pain often appear, followed by repeated wheezing, dyspnea, chest tightness, persistent cough and dyspnea, asthma accompanied by wheezing, and then expectoration; Bronchiectasis often has chronic cough, a lot of thick sputum and repeated coughing up blood.

(5) Tuberculosis: Symptoms such as low or high fever, emaciation, mild cough, chest pain, night sweats, increased heart rate and loss of appetite may occur.

(5) Cough with pneumonia: sudden onset, accompanied by high fever, chest pain, chills, coughing up rust-colored sputum.

(6) Cough caused by adverse drug reactions: About 20% of cough is caused by drugs. Common cough inducing drugs include angiotensin converting enzyme inhibitor, antiarrhythmic drug amiodarone, anticoagulant drugs heparin and warfarin, diuretic drug hydrochlorothiazide, antibacterial drug nitrofurantoin, anti-tuberculosis drug sodium p-aminosalicylate and so on. At this time, the application of antitussive drugs is ineffective, which often delays the illness. Therefore, it is necessary to stop taking medicine and change medicine in time.

Third, medication.

Although antitussive drugs are common drugs in daily life, we should pay attention to the following points when applying them:

(1) There are many causes of cough in clinic, and the key is symptomatic treatment. It is usually effective to use vasoconstrictor or corticosteroid nasal drops for cough caused by allergic rhinitis and sinusitis. For the elderly with a long history of smoking, there is no obvious incentive for irritating dry cough, so we should be especially vigilant to exclude lung cancer.

(2) Cough after a cold is often self-limiting, which can generally be relieved by itself, and antibacterial drugs are ineffective.

(3) If the cough persists for more than 1 week, accompanied by fever, rash, asthma and emphysema, you should go to the hospital or consult a doctor in time.

(4) Pay attention to the adverse reactions of antitussive drugs. If dextromethorphan can cause drowsiness, people who drive, work high above the ground or operate machines should use it with caution. Pregnant women, severe hypertension and people with a history of mental illness are prohibited. Benproperine has an anesthetic effect on the mouth, so it should be swallowed whole, not chewed. Penehyclidine should be used with caution in patients with glaucoma, cough with pulmonary congestion and cardiac insufficiency, pregnant women and lactating women.

(5) In the therapeutic dose range, the adverse reaction of codeine is obviously less than that of morphine, but excessive use of codeine can cause convulsion and excitement, and it is also addictive, so the dose and course of treatment should be controlled. It can cause drowsiness in lactating women, and it can cause serious adverse reactions in infants after taking it.

(6) In addition to medication, we should pay attention to rest, keep warm, quit smoking and drinking, and avoid irritating or spicy food.