Cough, cold and flu can often wreak havoc during the winter months, both due to the symptoms they cause to patients and the difficulty in differentiating between them. Both flu and the common cold are contagious respiratory illnesses caused by viruses and tend to be more widespread in winter months.1
Cough is a part of the body’s immune defence that is used to clear the airways of mucus and other irritants. Cough is a symptom and most often is caused by cold or flu. However, a number of other factors can cause cough include smoking, allergies, bronchitis, post nasal drip or acid reflux. Coughing is useful in clearing phlegm from the lungs, where it could otherwise cause infections such as pneumonia.2 Vaccination is the single most effective way to protect against flu. Unfortunately, there is no vaccination against the common cold. Flu vaccines are safe and effective, and are available through pharmacies nationwide.
Pharmacists have been administering flu vaccines in the community since 2011. Due to reducing antibodies and different flu strains each year, this vaccine is annual and is available between October and April. The effectiveness can vary from year to year, but it generally reduces the risk of getting flu by 40-60% and can also reduce severity of symptoms. The flu vaccine is recommended and is available for free for many patients, including those who are aged 65 years and older, aged 2-17 years, pregnant or have certain medical conditions. A full list of those eligible is available on the HSE website. Side effects are generally mild and can include soreness or swelling around the injection site, fever, aches and fatigue. Patients can treat these symptoms with rest and paracetamol. More serious side effects are rare and should be reported to the HPRA.3 Although cold and flu share similarities as both are contagious respiratory illnesses, they differ in many ways.
Flu is caused by influenza viruses, while colds can be caused by a variety of viruses including coronaviruses, parainfluenza and rhinoviruses.1 With regards to symptoms, cold and flu can also be similar but flu tends to be more severe than cold. The onset of cold is generally gradual, compared to the more sudden onset of flu – which usually appears within a few hours. Cold symptoms are usually in the upper respiratory tract and include blocked or runny nose, sneezing, cough, sore throat, loss of taste and smell, as well as fever and cough.4 Symptoms of flu include a sudden onset of fever, fatigue, body aches, difficulty sleeping, loss of appetite, dry cough and nausea.5 Both viruses can be unpredictable but symptoms generally start to resolve after one week. Flu is generally self-limiting in healthy individuals.
For certain individuals, flu and complications of flu can lead to serious illness. The most common complications are pneumonia and bronchitis. Patients that are aged 65 years or older, pregnant or have a long term medical condition are at an increased risk of complications from flu. As patients with asthma, COPD and heart failure are at high risk of complications, there may be a need to refer to a medical doctor for further treatment. Pharmacists should also be aware that patients may need to be referred on to a medical doctor if their symptoms don’t improve after 7 days or they have a weakened immune system due to HIV or chemotherapy.6 Cold and flu are generally treated based on symptoms. Cold or flu can’t be fully diagnosed based on symptoms alone, but laboratory tests are rarely used.
They are generally treated with over the counter medications that are used to provide symptomatic relief. Paracetamol and ibuprofen are both useful to treat aches and pains, as well as to reduce fever.6 Pseudoephedrine is a decongestant that provides symptomatic relief for congestion of the upper respiratory tract.7 Brompheniramine and diphenhydramine are both first generation antihistamines that can be used to treat symptoms of cold and flu including runny nose, sneezing and itchy/watering eyes.8, 9 Pharmacists should also counsel patients to get plenty of rest and sleep, keep warm, avoid smoking and to drink plenty of water.6 Flu can also be treated orally with Oseltamivir (Tamiflu) and by inhalation with Zanamivir (Relenza).
These are both antivirals of the neuraminidase inhibitor class, that have activity against both influenza A and B. Previously healthy patients with no underlying condition generally do not need antiviral therapy, unless the clinician feels the patient is at risk of developing complications. Pregnant women and patients who are deemed to be at risk of complications should be commenced on oseltamivir as soon as possible, even without laboratory confirmation of diagnosis. Efficacy of oseltamivir has been demonstrated when initiated within two days of onset of symptoms, with evidence suggesting that treatment can reduce the risk of mortality if commenced within five days of onset of symptoms. Zanamivir is not currently licensed in Ireland, but may be used as an unlicensed product to treat oseltamivir resistant influenza.10
Coughs generally will generally improve after a number of days. Patients should be counselled to drink plenty of fluids and get adequate rest. As with cold and flu, paracetamol and ibuprofen can be used to treat associated pain if appropriate.4 Cough syrups are available over the counter, with Benylin, Exputex and Bronchostop among the most common. Exputex is a mucolytic agent used to treat coughs characterised by excess mucus.11 Bronchostop is a traditional herbal medicinal that is used to provide symptomatic relief for a variety of coughs, exclusively based on long standing use.12 A wide range of Benylin cough bottles are licensed to treat a range of different types of coughs from 2 years plus.13 However, a hot lemon with honey drink is similarly effective as over the counter cough medicines. If a cough is caused by a cold or flu, antibiotics will not help to alleviate a patient’s symptoms. However, pharmacists may need to refer a patient for further medical treatment if the cough lasts for more than three weeks, the patient is coughing up blood or the patient is at risk of complications.4
References available on request
