Respiratory System

The respiratory system is the biological system that performs gas exchange from and to the body and includes organs of the airway passage the nasal cavity to the lungs, such as the pharynx, trachea, bronchus and lungs. Its main function is to supply the body with the oxygen needed for life, ie. filling up the lungs with fresh and removing carbon dioxide into the atmosphere.

Because the respiratory system is working non-stop and exposed to the outside environment, organs within the system are highly vulnerable to toxic substances that are present in the air around us, such as viruses, bacteria and pollens.

Reflex actions like secretion of mucus, sneezing and coughing are what the respiratory system does to get rid of certain foreign bodies. Macrophages are a type of cell that initiates defensive actions against viruses. The lungs are protected by macrophages which act as dust filters. Even with these defences, a weak body with low immunity also has low resistance to respiratory diseases.


Cold is one of the diseases that can strike at any time. Caused mainly by virus infection, cold symptoms are body ache, fever, cough, phlegm, sore throats, and runny, stuffy nose.

Common colds, classified as Cold 2 to 3, symptoms include acute inflammation in the upper respiratory tract – the nose, mouth, throat, and bronchial tubes. If minor, common colds take about a week or so to heal. However, colds can also be the source of other kinds of diseases like pneumomnia which can lead to serious complications if not treated early.

Different viruses, different symptoms

Runny nose, nasal congestion are symptoms of a head cold, but pain and swelling in the throat may indicate the presence of adenovirus, a type of virus that infects the upper respiratory tract.

Different symptoms with different viruses?

It is said that there are as many as 200 different types of cold viruses, with each virus targeting a different cell.

Choosing the right medicine for your symptom

In general, symptoms of cold are body ache, fever, cough, phlegm, sore throat, and runny, stuffy nose. But with a weakened respiratory system, the patient may be vulnerable to more serious effects or other diseases, so early
recovery is important as is choosing the right medication.


Cold remedies

    You can try antihistamines to clear nasal congestion and sneezing; while antipyretic analgesics (eg. paracetamol) help to reduce fevers. Some Chinese herbs and medicines also help to relieve cough.

  • Nasal congestion
    Sneezing, runny nose, and nasal congestion. These are the three symptoms that signal the start of colds. Usually antihistamines will relieve the symptoms and suppress allergic reactions. Nasal decongestion medication is safe in the early stages, but some people tend to use too much of it, making the nasal cavity over sensitive. As such you should be cautious about long-term continuous use.

  • Sore throat
    By using mouthwash or taking lozenges with sterilising properties, it’s possible to prevent a full-scale cold when you have a sore throat.
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  • Severe cough and phlegm
    Probably the most annoying symptoms of a cold are cough and phlegm. There are many medications to relieve these but take care not to over-consume them. However, clear your phelgm as much and as often as possible, because as long as phelgm stays in the respiratory tract or body, bacteria also remains.

  • Non-drowsy cold medicine
    Nowadays, non-drowsy cold medication, including some herbal Chinese remedies are widely available, and are suitable for use while at work.
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  • Fever
    The onset of fever is a signal that your white blood cells are doing their job of fighting viruses, using a higher body temperature as a weapon. But this heat defence reaction also causes the body to be weak from exhaustion. Antipyretic analgesics such as paracetamol is used to help prevent this exhaustion. Lots of liquid intake, along with Vitamin C also make up for lost strength during your recovery.

Typical ingredients of cold medicines

  • Headache and fever
    Antipyretic analgesic lowers body temperature, relieves pain and reduces sore throats and headaches.
    The main ingredients: paracetamol, aspirin, acetaminophen, anti-isopropyl Lee Pirin, ibuprofen, ethenzamide, salicylamide.
    Caffeine additives make pain relievers more effective in treating headaches and is a common ingredient in many headache medications. It also helps the body absorb headache drugs more quickly, bringing faster relief.
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  • Cough
    Dextromethorphan hydrobromide, tipepidine hibenzate, dihydrocodeine phosphate, dl-methyl ephedrine hydrochloride all help to relieve cough by suppressing the cough.
  • Runny nose, nasal congestion, sneezing
    Diphenhydramine hydrochloride, clemastine fumarate, carbinoxamine maleate, chlorpheniramine maleate, triprolidine hydrochloride bind to chemical messengers to stimulate antihistamine ingredients to relieve allergy symptoms.

  • Phlegm
    Guaifenesin, potassium guaiacolsulfonate loosen mucus and phlegm making them easier to expel.

  • Vitamin supplements
    Vitamins C, B1 and B2 supplements should be taken as these are easily depleted during a cold.

People who are vulnerable to colds

  • People who are stressed and fatigued.
    When stressed and tired, the body resistance is low and susceptible to catching a cold. Those vulnerable should nourish their bodies with herbal tonics or take supplements like Vitamin E for its antioxidant properties and Vitamin C for its immunity properties. Sufficient sleep and rest are of course, vital.
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  • Elderly
    Along with a lower body resistance, an elderly person will also have weakened functions of expelling phlegm and coughs will also be more painful. In addition, viruses and bacteria can enter the lungs to cause acute pneumonia. For those with chronic diseases or bedridden elderlies in particular, a simple cold can have serious consequences.Such persons should be more cautious in public places to avoid getting infected by people with colds because fever and some symptoms of cold may not be noticeable. For those who are on prescription drugs for other conditions, consult your doctor before taking any medications for colds.

  • Children
    Children tend to get infected with the flu bug at school. Observe your child well during the “flu season”. If your child’s face is flushed red, it may not always be a symptom of fever, unless a runny nose or sore throat accompanies it. If there’s a fever, an antipyretic analgesic for children will help your child to sweat the fever out, but keep him hydrated with water or a sports drink. And if the fever continues, visit the doctor as soon as possible.

The difference between “flu” and “cold”

It’s not surprising that many people cannot tell the difference between having caught a cold and having influenza. The fact is, a flu virus and cold virus are not quite the same, even though some of the symptoms are similar. It’s important to know the difference between flu and cold symptoms. A cold is a milder respiratory illness. While cold symptoms can make you feel bad for a few days, flu symptoms can make you ill for up to a few weeks. The flu can also result in serious health problems such as pneumonia and may land you in the hospital, especially for people with pre-existing chronic illnesses such as liver disease or diabetes.

Cold. Affects mainly the respiratory tract. Symptoms include runny and stuffy nose, sore throat, fever (37ºC to 38ºC) and headache. Recovery time is about one week.

Influenza. The influenza virus can cause infections and lead to complications such as bronchitis and pneumonia. Symptoms include sudden high fever (38ºC to 40ºC), followed by severe headache, muscle and joint aches and severe fatigue and these symptoms may go on for up to a few weeks. Children and elderly should take extra precautions as exhaustion can pose dangerous consequences.


Sore throat

The throat is one of your body’s front line contact with foreign objects of all kinds, from food, drink and air. Because of that, any change in your body’s resistance can cause bacterial infection. A sore throat is an inflammation of the pharynx, or throat, and can be divided into chronic pharyngitis and acute pharyngitis.

Acute pharyngitis one of the symptoms of cold, when bacterial infection breaks the resistance of the pharyngeal mucosa (mucous of the throat).

Chronic pharyngitis is caused by repeated or acute pharyngitis, and nasal discharge flows into the throat because of the inflammation of the paranasal sinuses.

What causes pain

Sore throats can also be caused by excessive smoking, drinking, talking and dry air. But an inflammation of the throat signals a viral or bacterial infection.


Type of symptoms

When the whole throat hurts this condition is known as pharyngitis, where there’s pain and congestion. Acute pharyngitis can become chronic pharyngitis if condition is not improved.

Swelling tonsils

Tonsils play an important role in preventing viral and bacterial infection from outside but this role is often weakened by physical fatigue and allergic reactions, and accompanied by fever.

Hoarse throat

This is when the throat is swollen by inflammation and is painful when swallowing or gargling. At this stage the inflammation has spread to the larynx. In addition, voice is affected. The larynx is the entrance to the respiratory system, so care should be taken with regards to breathing through the mouth.



Over-eating, over-working, excessive drinking, lack of hydration, lack of sleep… these are social habits that often trigger the onset of flu and colds. You may also want to avoid straining your throat when singing or talking.


A little swelling can get worse if left untreated. To prevent viruses from gaining a foothold, you could try gargling with mouthwash as soon as possible, or take throat drops. For sterilisation and disinfection of the throat, spray type of medication is also effective.


A cough is a sudden and often repetitively occurring reflex which helps to clear the respiratory passages from secretions, irritants and foreign particles. When inflammation is extended to the trachea (windpipe), secretions will be increased (phlegm). Coughing is a natural reflex to excrete the phlegm, sometimes to the extend of causing disturbances to daily activities or sleep.

Most coughs with phlegm are attributed to colds. With medication and rest, it’s not something to be worried about. But in cases where there’s breathing difficulty and the phlegm is yellow, consult a doctor immediately as it could be a sign of lung disease. See a doctor also if a wet cough continues for a few months; it could be chronic bronchitis.

Acute Bronchitis

Bronchitis is more commonly associated with respiratory disease than with common cold or influenza. It can occur sometimes by foreign stimuli like the smoke or fumes of chemical substances. Cough, accompanied by white or colourless phlegm and high fever.

Prolonged coughs

The main symptom of this is prolonged cough with phlegm, starting in the early morning and getting worse at night. This is due mainly to smoking, and can be accompanied by a whistling sound when breathing which could signal the presence of bronchial asthma.


This is an inflammation of the tonsils most commonly caused by viral or bacterial infection. Symptoms may include sore throat and fever. Most people recover completely, with or without medication. In 40%, symptoms will resolve in three days, and within one week in 85% of people.

Care when having cough and/or phlegm

When a cough continues for a long time, it can be a huge drain on the body. Rest, and enough rest is really important. Make sure the room is warm. It’s also easier to sleep when the upper body is placed higher. A gentle back rub would aslo prove soothing.

Pollutants such as household dust, smoke, pollens all contribute to coughing. In addition, the cold and dry air from the air conditioner is also a contributor. If a humidifier is not available in an air conditioned room, you could place a wet towel near to you to help moisten the air around you.

Cough syrups, over-the-counter drugs and pastilles and lozenges are very common to relief coughs and sore throats, so have them handy.