Respiratory Medicines

Decongestants

Indications • runny nose • stuffy head • sore throat • some ear pain

Action - binds to alpha-1 receptors on blood vessels in nasal membranes

Decongestants

Effects• vasoconstriction• decrease swelling• dries nasal passages• decrease congestion• unclog eustachian tubes

Administration• oral• topical

Decongestants

Examples• (Pseudoephedrine) - Sudafed, Claritin-D• (Phenylpropanalomine) – Banned by FDA in

2000

Decongestants Adverse effects

• headache• dizziness• nervousness• nausea• increase blood pressure

** slight stimulant effect• Pseudoephedrine banned by USOC

Antihistamines Indications

• respiratory allergies• S/S – sneezing, itchy watery eyes, runny nose,

congestion

• systemic allergies• allergic conjunctivitis• sedation (sleeping medicines)• motion sickness• nausea• vertigo

Important definitions

What is histamine? Endogenous chemical stored in mast cells involved in normal regulation of physiologic functions

What is an allergen? An ordinarily harmless substance that the body recognizes as foreign

The result? The body produces antibodies (IgE) to fight the “foreign substance” causes the release of histamine

Effects of histamine - redness, itching, watery eyes, vasodilation

Antihistamines

Action - blocks H1 receptor sites by attaching to mast cells in nasal passages

Effects - prevents a histamine response• dries membranes• shrinks swollen tissues• decreases redness• decreases itching

Antihistamines

Adverse effects• dry mouth & throat• heart irregularities• dizziness• blurred vision• decrease mental alertness• SEDATION

• alcohol increases the effects

Antihistamines

Examples• (Diphenhydramine) - Benadryl, Tylenol PM• (Doxylamine Succinate) - Unisom• (Clemastine) - Tavist• (Promethazine HCl) - Phenergan• Claritin• Allegra• Zyrtec

** many antihistamines also contain a decongest.

Antitussives - (Cough Suppressant)

Suppress a non-productive cough Types & Effects

• narcotic - suppress cough reflex• non-narcotic - inhibit irritating effects of

histamine, decrease sensitivity to stimuli Adverse effect – sedation, interactions

w/other meds Examples

• (Dextromethorphan)• (Codeine)

Cough Expectorant

Recommended for productive coughs Facilitate production and ejection of mucus Decrease viscosity Examples

• Guaifenesin

Explain the logic of combining an expectorant with a suppressant?????

Fixed-Ratio Combination Products1. Some active ingredients not needed

2. Not possible to formulate dosage to person

3. Ingredients are sometimes less than therapeutic doses

4. Risk of interaction

5. Cost

Zinc

Inhibit the production of viruses Recently used to decrease symptoms of the

common cold