This lecture by Dr. Darin Ramsey occurred on Monday, October 4th and Monday October 11th.
Back to RX 415 - Self Care
Required reading includes:
- Cough and Cold medicine use in pregnancy. Pharmacist’s Letter/Prescriber’s Letter 2006r;22(11):221122.
- Alternatives to cough and cold medications for children. Pharmacist’s Letter/Prescriber’s Letter 2008;24(1):240111.
- Concerns about OTC cough and cold products in children. Pharmacist’s Letter/Prescriber’s Letter 2007;23(11):231106.
Describe the etiology and pathogenesis of cough and coldEdit
EtiologyEditThere are about 30 viral strains that invade teh nasal and bronchial epithelial cells to cause the common cold. The viruses most commonly responsible for the common cold are:
- Respiratory syncytial virus
- Influenza virus
- Parainfluenza virus
In order to produce infection, the rhinovirus must penetrate the protective mucous that covers the nasal epithelium. Rhinovirus infection leads to the releas of various inflammatory mediators such as: prostaglandins, leukotrienes, and kinins, which are involved in the symptoms
- Nasal congestion
- Runny nose
- Sore Throat
Evidence favors direct contact or aerosol transmission as the main routes of infection. These viruses can survive up to 3-4 hours outside the body. Within 8-12 hours of viral entry into the nose or eye, the inflammatory mediators & the parasympathetic nervous system reflex mechanisms lead to
- Nasal congestion
- Stimulation of Cough and Sneezing reflexes
"Catching" a cold often occurs by having contact with the hands of an infected person as well as obejcts that the infected person has touched. To avoid infection, experts advise
- Washing hands frequently with soap and hot water, and if this is not available using alcohol based gels such as Purell are at least as effectifve as hand washing
- Keeping hands away from the eyes and nose
- Washing contaminated objects or surfaces
- Using disposable tissues instead of a handkercheif
- Covering a cough or sneeze (with one's shoulder/sleeve)
It is a myth that getting chilled or wet will cause someone to get a cold. However, colds are more common in winter due to:
- Lower humidity - which allows cold viruses to survive longer
- Cold weather also dries the lining of the nasal passages, making viral entry easier
- People spend more time indoors and are exposed to more viruses
Several factors affecting susceptibility and transmission of viruses have been identified
- Poor nutritional status
- increased population
- Sedentary lifestyle
- emotional stress
Identify the symptoms of the common coldEdit
Individuals may begin to notice symptoms within 1-2days after contact.
A sore throat is followed by a thin, water discharge, and sneezing. Within 1-2days, the thin watery discharge may become thick and purulent.
A dry, nonproductive cough may develop between days 3 and 5, often evolving into a productive cough. With time, the water discharge is transformed to a thick, tenacious consistency
Generally, the most annoying and troublesome symptoms of the cold lsat approximately 4-5 days, with the syptoms gradually diminishing and disappearing after approximately 7-13 days.
There are 5 symptoms areas where a pharmacist can recommend treatment
- Sore Throat
Distinguish the differences between the cold and the fluEdit
If a patient becomes sick quickly, has joint pains & body aches, or has a high fever, chances are it is the flu, which is caused by the influenza virus
The best way to prevent the flu is to get the yearly influenza shot
Like the common cold, there is NO cure for the flu, and antibiotics are NOT helpful in treating the flu.
Distinguish the difference between productive and non productive cough and between acute, subacute, and chronic coughEdit
Productive (Wet) CoughEdit
Expels secretions from the lower respiratory tract that if retained, could impair ventilation and the lungs' ability to resist infection. Secretions may be:
- Clear - bronchitis
- Purulent - Bacterial infection
- Discolored - Yellow
Nonproductive (Dry/Hacking) CoughEdit
Serves no physiologic purpose Caused by:
- Viral respiratory tract infections
- Atypical bacterial pathogens
- Gastroesophageal reflux disease (GERD)
- Drug Induced (ACE-inhibitors, Beta blockers)
Duration of 3 weeks or less
Commonly caused by a viral upper respiratory tract infection (common cold)
Duration of 3 to 8 weeks
Commonly caused by postinfectious cough, bacterial sinusitis, and asthma
Duration longer than 8 weeks
The most common causes of chronic cough in nonsmokers are postnasal drip syndrome, asthma, and gastroesophageal reflux diease
Identify patients that should be excluded from self treatment and should be referred to a doctorEdit
Describe the mechanism by which expectorants, antitussives, decongestants, & antihistamines workEdit
Facilitate the removal of mucous and other irritants from the respiratory tract & decrease the viscosity of thickened secretions. Expectorant activity is best obtained by adequate of fluids. (8-10 glasses of water/day) Guaifenesin is the only expectorant that has demonstrated safety and efficacy for self-administration by the FDA
- Dose: 200-400 mg q4h (Robitussin)
- Mucinex is the 1st and only single-ingredient extended release guaifenesin product approved OTC
- Mucinex is a 600mg tablet that provides 100mg of the drug rapidly and 500mg extended release for up to 12 hours.
- Adverse effects: occasionally causes gastric disturbance, nausea, & vomiting
Because of the therapeutic endpoints, some clinicians question the rationale for combined use in the same product of an antitussive and an expectorant (E.g. Robitussin DM) If symptoms worsen or no improvement noted in 7 days, consult a healthcare provider. Nonproductive coughs are best suppressed with antitussives, productive coughs are best assisted with expectorants.
Patients with dry, nonproductive coughs are candidates for therapeutic cough suppression. Antitussives include:
The standard against which all other antitussives are measured.
- 6-12 years of age: 5-10mg q4-6h (max 60 mg/day)
- >12 years of age: 10-20mg q4-6h (max 120 mg/day)
Potential for abuse has been observed. Therefore it is a schedule 5 drug. OTC sale in cough syrups may be restricted in some states. Robutissuin AC is one such product that includes codeine. (Guaifinesin 100mg & Codeine 10mg per 5ml)
- loss of appetite
Contraindications: Children under 6 are vulnerable to serious adverse effects of respiratory arrest, coma, and DEATH reported following single doses of 5-12 mg/kg
Synthetic non-narcotic agent having no analgesic or addictive properties.
- 10-20 mg q4h
- 30 mg q6-8h
For cough suppression, it is as effective as codeine on a mg-to-mg basis.May be indicated in persons whom adverse effects of codeine are particularly bothersome. Usual therapeutic doses do NOT cause significant effect on respiratory or cardiovascular function.
- GI upset
Abuse: Under indiana law patients must be 18 and sign to purchase
An antihistamine and antitussive agent
Dose: 25mg q4h
Part of the antitussive action may be mediated through anticholinergic activity. It is also a great nighttime agent to induce sleep in a patient with a nonproductive cough.
Adverse effects: Sedation and Anticholinergic effects as discussed under antihistamines.
Camphor and Menthol
FDA approved for alleviation of cough, available in topical ointments and steam inhalants
Produce a sensation of coolness and a local anesthetic effect on the respiratory tract by stimulating cold sensory receptors.
Menthol is also effective as an antitussive and is available in oral lozenges
- VICK'S Vaporub
- Hall's Mentho-Lyptus