Community Pharmacy Respiratory system Lecture 3

THE COMMON COLD

The Common Cold The condition has no specific cure and is self-limiting with two-thirds of sufferers recovering within a week

Prevalence and epidemiology The common cold is extremely prevalent and like cough is caused by viral URTI. Children contract colds more frequently than adults with on average five to six colds per year compared to two to four colds in adults, although in children this can be as high as 12 colds per year.

Aetiology Rhinoviruses (accounting for 30- 50% of all cases). Coronaviruses. Parainfluenza virus. Respiratory syncytial virus. Adenovirus.

Differential Diagnosis Whilst it is likely that a patient will have a common cold, severe colds can mimic the symptoms of flu, which is the only condition of any real significance that has to be eliminated before treatment can be given, although secondary complications can occur.

Clinical features of the common cold Following an incubation period of between 1 and 3 days (although this can be as short as 10-12 hours), the patient develops a sore throat and sneezing, followed by profuse nasal discharge and congestion. Cough and UACS commonly follow. In addition, headache, mild to moderate fever (<38.9·C;)

Condition To Eliminate Likely Causes Rhinitis (A blocked or stuffy nose, whether acute or chronic). Acute rhinosinusitis. Acute otitis media.

2.Rhinosinusitis Rhinosinusitis (formerly sinusitis) is inflammation of one or more of the paranasal sinuses. Following a cold, sinus air spaces can become filled with nasal secretions, Bacteria - commonly Streptococcus and Haemophilus - can then secondarily infect these secretions. It is clinically defined by at least two of the following symptoms: • Blockage or congestion • Discharge or UACS • Facial pain or pressure • Reduction or loss of smell.

3. Acute Otitis Media This is commonly seen in children following a common cold and results from the virus spreading to the middle ear The overriding symptom is ear pain but the child may rub or tug at the ear and be more irritable. The pharmacist should offer symptomatic relief of pain with either paracetamol or ibuprofen. If symptoms persist referral to the GP for possible antibiotics

Condition To Eliminate (Unlikely Causes) 1- INFLUENZA ' flu' season tends to be between December and March, whereas the common cold, although more common in winter months, can occur at anytime. The onset of influenza is sudden and the typical symptoms are shivering, chills, malaise, marked aching of limbs, insomnia, a non-productive cough (cough in the common cold is usually productive), and loss of appetite. Influenza is therefore normally debilitating.

Over-the-Counter Medication Antihistamines Sympathomimetics Multi-ingredient preparations. Alternative therapies: A. Zinc lozenges B. Vitamin C C. Echinacea D. Vapour inhalation (key to symptom resolution, and not any additional ingredient that is added to the water). E. Saline sprays

Sympathomimetics Constrict dilated blood vessels and swollen nasal mucosa, easing congestion and helping breathing. Interact with monoamme oxidase inhibitors (MAOIs) (e.g. phenelzine, tranylcypromine and moclobemide), which can result in a fatal hypertensive crisis. The danger of the interaction persists for up to 2 weeks after treatment with MAOis is discontinued. Systemic sympathomimetics can also increase blood pressure, which might alter control of blood pressure in hypertensive patients and disturb blood glucose control in diabetics.

SYMPATHOMIMETICS (CONTINUED) Side effects of sympathomimetics are insomnia, restlessness and tachycardia. Patients should be advised not to take a dose just before bed-time because their mild stimulant action can disturb sleep. Sympathomimetics (oral or nasally administered) should not be given to children under 6 years of age and for those aged between 6 and 12 duration of treatment should be limited to a maximum of 5 days.

A. Systemic Sympathomimetics Phenylephrine Pseudoephedrine

B. Nasal Sympathomimetics Safest route of administration. They can be given to most patient groups, including pregnant women after the first trimester and patients with pre-existing heart disease, diabetes, hypertension and hyperthyroidism. A degree of systemic absorption is possible, especially when using drops, as a small quantity might be swallowed, and therefore they should be avoided in patients taking MAOIs. All topical decongestants should not be used for longer than 5 to 7 days otherwise rhinitis medicamentosa (rebound congestion) can occur.