Expert Consensus on Standardized Diagnosis and Treatment of Common Cold (Introduction) I. Etiology 1. Etiology: Most common colds are caused by viruses. Rhinoviruses are the most common pathogens causing common colds, and other viruses include coronaviruses, parainfluenza viruses, and respiratory syncytial viruses. Risk factors: Risk factors for colds include seasonal changes, crowded environments, sedentary lifestyles, age, smoking, malnutrition, stress, excessive fatigue, insomnia, and low immunity. Clinical manifestations: Colds often develop in seasonal changes and winter and spring seasons, with an acute onset. Early symptoms are mainly nasal symptoms, such as sneezing, nasal congestion, watery nasal discharge, pharyngeal discomfort or dryness, itchy or burning sensation in the early stage. 2-3 d later, it turns into thick snot, with sore throat or hoarseness, and sometimes hearing loss due to pharyngitis, as well as symptoms of tearing, dullness of the sense of taste, poor breathing, cough, and small amount of sputum. Sometimes there may be hearing loss due to pharyngitis. Generally, there is no fever and systemic symptoms, or only low-grade fever. In severe cases, in addition to fever, there may be malaise, chills, aches and pains in the limbs, headache, loss of appetite and other systemic symptoms. The common cold without complications can be cured in 5-7 d. The elderly and children are susceptible to complications. Elderly people and children are prone to cold complications. If accompanied by underlying diseases, the clinical symptoms of the common cold are more severe and prolonged, and complications are likely to occur, prolonging the course of the disease. Physical examination reveals nasal mucosal congestion, edema, and secretions, mild pharyngeal congestion, and no abnormalities in the chest. Those with underlying diseases or complications can be detected with corresponding signs. Laboratory examination 1, peripheral blood: the total number of leukocytes is not high or low, the proportion of lymphocytes is relatively increased, and the total number of leukocytes and lymphocytes can be decreased in patients with severe diseases. Virology: Virology examination of common cold is generally not carried out in clinic, and is mainly used for epidemiological research. Diagnosis of common cold is mainly based on typical clinical symptoms, and diagnosis is confirmed on the premise of excluding other diseases. Differential diagnosis 1, influenza (hereinafter referred to as influenza): acute onset, highly infectious, with systemic symptoms of poisoning, respiratory symptoms are mild. Elderly people and people with chronic respiratory diseases and heart disease are prone to complications of pneumonia. 2, acute bacterial sinusitis: the causative organisms are mostly Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus, Escherichia coli and Escherichia coli, etc., and mixed infections are mostly seen in the clinic. Symptoms are often aggravated after viral upper respiratory tract infections. The main symptoms are nasal congestion, increased purulent nasal discharge, decreased sense of smell and headache. Acute sinusitis patients may be accompanied by fever and generalized symptoms. 3, allergic rhinitis: seasonal and perennial, mostly in contact with allergens (such as pollen, etc.) symptoms, the main symptoms of paroxysmal sneezing, watery nasal discharge, after the attack, such as healthy people. Only nasal symptoms or fatigue, generally no fever and other systemic symptoms, and the course of the disease is long, perennial recurrence or seasonal aggravation. 4, streptococcal pharyngitis: the main causative organism is A-type beta-hemolytic streptococcus. Its symptoms are similar to viral pharyngitis, fever can last 3-5 d, and all the symptoms will be relieved in 1 week. It occurs in winter and spring seasons; it is mainly characterized by pharyngeal inflammation, which may be accompanied by pharyngeal discomfort, itchiness, burning sensation, sore throat, etc. It may be accompanied by fever and malaise, etc. On examination, there is obvious pharyngeal congestion and edema, and the submandibular lymph nodes are enlarged and have tenderness. The diagnosis of streptococcal pharyngitis mainly relies on the culture of pharyngeal swab or rapid antigen detection. 5, herpes pharyngitis: the onset of the season mostly in the summer, common in children, occasionally seen in adults; the degree of sore throat is more serious, mostly accompanied by fever, the duration of the disease is about 1 week; there is pharyngeal congestion, soft palate, palatine, pharyngeal and tonsillar surfaces of grayish-white herpes and superficial ulceration, circumferentially with the encircling red halo; the virus isolation of Coxsackie Virus A. Treatment (a) principles of treatment Since the cold is not yet a specific antiviral drugs, it is necessary to treat symptomatically, relieve colds and flu. Therefore, symptomatic treatment should be given to alleviate the symptoms of cold and flu, and attention should be paid to rest, proper supplementation of water, and keeping indoor air circulation to avoid secondary bacterial infection. (ii) General treatment: Rest appropriately; patients with fever, serious illness or old and weak patients should rest in bed; quit smoking, drink more water, eat a light diet, and maintain nasal, pharyngeal and oral hygiene. Oral medication should be preferred for the treatment of cold and flu patients, and blind intravenous rehydration should be avoided. Intravenous rehydration is only applicable to the following situations: (1) the patient’s existing underlying diseases are aggravated due to the cold, or complications arise, requiring intravenous drug administration; (2) the patient needs to replenish water and electrolytes due to dehydration and electrolyte disorders caused by severe diarrhea or high fever; (3) the patient is unable to eat due to gastrointestinal discomfort and vomiting, and needs rehydration to maintain the body’s basal metabolism. (C) Drug treatment The drug treatment of common cold should be based on symptomatic drugs. The types of drugs commonly used in clinical practice are as follows: 1. Decongestants: these drugs can make the swollen nasal mucosa and sinuses of cold patients vasoconstriction, which can help to alleviate cold-induced symptoms such as nasal congestion, runny nose and sneezing. Pseudoephedrine selectively constricts blood vessels in the upper respiratory tract and has less effect on blood pressure, making it the most commonly used decongestant in patients with the common cold. Other vasoconstrictor drugs such as ephedrine, if used in excess, can lead to increased blood pressure, etc., and special attention should be paid. In addition to oral administration, these drugs can also be used directly as nasal drops or nasal spray, but generally should not be used continuously for more than 7d. 2. Antihistamines: these drugs have an anti-allergic effect, inhibit the dilatation of small blood vessels by blocking the histamine receptor to reduce vascular permeability, which can help to eliminate or alleviate the symptoms of sneezing and sneezing of patients with common colds. However, common adverse reactions to this class of drugs include drowsiness, fatigue, etc., and should be used with caution by workers in industries such as car and boat driving, ascent work or operation of precision instruments. First-generation antihistamines, such as chlorpheniramine maleate and diphenhydramine, have the ability to cross the blood-brain barrier, penetrate human central nerve cells and bind to histamine receptors. Because they have a certain degree of anticholinergic effect, they can help to reduce secretions and alleviate the symptoms of coughing, and are therefore recommended as the first choice of medicine for the common cold. Second-generation antihistamines, despite their non-drowsy, non-sedating virtues, do not suppress cough because of their lack of anticholinergic effect. Antihistamine nasal sprays have stronger local effects and fewer systemic adverse effects. 3, cough suppressants: two categories: (1) central cough suppressants: morphine alkaloids and their derivatives. (1) dependent cough suppressants: such as codeine, can directly inhibit the medulla oblongata center, cough suppressant effect is strong and rapid, and has analgesic and sedative effects. Because of its addictive properties, it is only used briefly when other treatments are ineffective. ② non-dependent cough suppressants: mostly synthetic cough suppressants. Such as dextromethorphan, is currently the most widely used clinical cough suppressant, the effect is similar to codeine, but no analgesic and sedative effect, the therapeutic dose of the respiratory center has no inhibitory effect, there is no addiction. A variety of non-prescription compound cough suppressants contain this product. (2) peripheral cough suppressant: through the inhibition of the cough reflex arc in the receptors, afferent nerves and effectors in a link and play a role in cough suppression. These drugs include local anesthetics and mucosal protective agents. ①Narcotics: isoquinoline alkaloids contained in opioids, with effects comparable to those of codeine, no dependence, and no inhibitory effect on the respiratory center. It is suitable for coughs caused by different reasons. (ii) Benadryl: non-narcotic cough suppressant, can inhibit peripheral afferent nerves, can also inhibit the cough center. (* Compound licorice tablets 3 tablets tid contained, chewed or crushed punch) 4, expectorants: expectorant treatment can improve the cough on the clearance of airway secretions. The mechanism of action of expectorants includes: increase the amount of secretion discharge, reduce the viscosity of secretion, increase the clearance function of cilia. Commonly used expectorants include guaiacol glyceryl ether, ambroxol, bromoacetin, acetylcysteine, carbocysteine, etc.; among them, guaiacol glyceryl ether is a commonly used ingredient of compound cold medicines, which can stimulate the gastric mucous membrane, reflexively cause an increase in airway secretion, reduce the degree of mucus, and have a certain diastolic bronchial effect, to achieve the effect of increasing the discharge of mucus. Often used in conjunction with antihistamines, cough suppressants, decongestants. 5, antipyretic and analgesic drugs: mainly for common cold patients with fever, sore throat and generalized pain and other symptoms. This kind of drugs such as acetaminophen, ibuprofen and so on. Acetaminophen is one of the more commonly used drugs, but it should be noted that acetaminophen overdose may cause liver damage or even liver necrosis. Ibuprofen has been reported to increase the severity of infection. Most of the cold and flu medicines on the market are compound preparations, although there are many varieties with different names, the ingredients of their formulas are the same or similar, and the effects of the medicines are very similar. Therefore, compound anti-cold and flu medicines should only be chosen as one of them, and taking more than two medicines at the same time can lead to repeated medication, overdose, and increase the incidence of the above mentioned adverse drug reactions. Some research data show that the early only nasal symptoms of cold and flu patients, taking pseudoephedrine hydrochloride and paracetamol on the first day, nasal congestion, runny nose, sneezing, tearing symptoms have improved, after 4d of the above symptomatic improvement have reached about 90%, indicating that this combination can rapidly improve or eliminate nasal symptoms. Therefore, pseudoephedrine and paracetamol are recommended as a classic combination for the treatment of early colds with only nasal symptoms. When symptoms such as cough, generalized body aches and fever are present on top of nasal khat symptoms, cold remedies containing cough suppressants and antipyretic and analgesic ingredients are recommended. Course of treatment: Since cold is a self-limiting disease, the medication for common cold should not be more than 7d. If the above symptoms have not significantly improved or disappeared after 1 week, the patient should go to the hospital for a clear diagnosis in time and be given further treatment. (iv) Anti-infective drugs and common cold The common cold is a self-limiting disease, antibacterial drugs are not recommended to treat the common cold, and antibacterial drugs are ineffective in preventing bacterial infections. Only when combined with bacterial infections, the application of antibacterial drugs will be considered, such as: sinusitis, otitis media, pneumonia and so on. There are no specific antiviral drugs for the common cold, and the common cold does not need to be treated with antiviral drugs. Excessive use of antiviral drugs significantly increases the risk of associated adverse effects. (v) Treatment of special populations Over-the-counter cold medications should not be used for the common cold in young children under 2 years of age because their safety has not been confirmed. If their symptoms must be controlled with medications, they should use medications approved for use in young children by the State Pharmaceutical Administration. for children aged 2-5 years, the dose of pseudoephedrine should be 1/4 of that for adults; for children aged 6-12 years, the dose of pseudoephedrine should be 1/2 of that for adults, and syrups or suspensions should be used as much as possible. Salicylates such as aspirin should be used with caution in children with fever, as the latter can induce Reye’s syndrome and lead to death in children. Cold and flu medications should be used with special caution in pregnant and lactating women. Pregnant women should try not to use aspirin, diclofenac sodium, diphenhydramine, ibuprofen, dextromethorphan, etc., which may affect fetal development or lead to prolonged pregnancy. Guaiacol glyceryl ether is contraindicated during the third trimester of pregnancy. Nursing women try not to use Benadryl, chlorpheniramine maleate, amantadine, etc., because these drugs can affect young children through breast milk. Cold and flu medications containing acetaminophen, aspirin, ibuprofen, etc. should be used with caution in those with hepatic or renal insufficiency, thrombocytopenia, bleeding symptoms, and/or a history of perforated ulcer disease. Cold and flu medicines containing chlorpheniramine maleate and diphenhydramine should be used with caution for those who are engaged in driving, working at heights, or operating precision instruments, because the first-generation antihistamines have an anticholinergic effect that affects neuron or neuromuscular junction conduction, which can lead to transient disorders of nerve function and lack of concentration. Uncontrolled severe hypertension or heart disease and patients taking monoamine oxidase inhibitors at the same time, prohibited cold and flu medicines containing pseudoephedrine ingredients, hyperthyroidism, diabetes mellitus, ischemic heart disease and prostate hypertrophy patients, cold and flu medicines containing pseudoephedrine ingredients should be used with caution. Pseudoephedrine is not recommended as a topical medication for patients with glaucoma. Cold and flu medications containing codeine and dextromethorphan should be used with caution in patients with chronic obstructive pulmonary disease and respiratory insufficiency in severe pneumonia because the central cough suppressant effects of codeine and dextromethorphan can interfere with sputum expulsion. In conclusion, physicians should develop individualized treatment strategies according to the characteristics of different populations and different symptoms of common cold, especially for special populations.