• What are the general causes of rhinitis and rhinorrhoea?

allergies, cold, chemical or drug damage, cold air or physical damage.

• Which drug groups can be used for the treatment of rhinorrhoea? Name examples from each group.
  1. α1-agonists – phenylephrine
  2. Antihistaminic and antimuscarinic drugs - Brompheniramine
  3. Corticosteroids - Prednisone
  4. Anti-allergy drugs – Sodium cromoglycate
  5. Mucolytics – Mesna
  6. Diverse Drugs – Normal salt solutions and volatile oils
• How do the decongestants differ with respect to the mechanism of action and duration of action?  How are they administered typically?

• Decongestants cause vasoconstricion of mucosal blood vessels that reduces oedema of nasal mucosa. Local Decongestants have fewer side effects, eg oxymetazoline (drops). Short acting drugs have a duration of 4 to 6 hours, intermediate acting drugs have a 8 to 10 hour duration and long acting drugs have a 12 hour duration.
• What is rhinitis medicamentosa?  How is it treated?

Rhinitis medicamentosa (privinism) is a condition that may present following chronic treatment with decongestants, where the permanent vasoconstriction with poor local blood supply leads to damage of the mucous membranes of the nose with permanent inflammation and swelling, as well as deregulation of the α-adrenergic receptors on the blood vessels, rendering them unresponsive towards the α-agonists.

It is treated by stopping the previous treatment and receiving local corticosteroids therapy

• How does the first and second generations of antihistamines differ with respect to the mechanisms according to which rhinitis and rhinorrhoea are relieved?  What are the advantages of the second generation of antihistamines?  Why should they not be used to relieve cold rhinitis?

• The first-generation antihistamines block muscarinic receptors.
• The second generation does not block the muscarinic receptors.
• The advantages of the second-generation antihistamine is that they are useful in the long-term or short-term treatment of allergic rhinitis.
• They should not be used to relieve cold rhinitis is because histamine plays no part in cold rhinitis.
• When are corticosteroids, anti-allergic drugs, mesna and normal salt solution valid and how are they administered? 

• Corticosteroid nasal sprays are weakly absorbed systemically, but can sometimes, in large doses, cause systemic side effects.
• Anti-allergic drugs - The use of sodium cromoglycate as a nasal spray is very effective for the prophylactic treatment of allergic rhinitis
• Mesna - Topical mesna (nasal spray) is especially meaningful to use when nasal secretion is sticky
• Normal salt solution – effective as nose drops. They are valid when humidification of dry, inflamed mucous membranes of the nose during colds, dry weather, allergy (hay fever), nose bleeding, overuse of decongestants and other irritations is necessary.