Pharm- HEENT- antitussives

inhibit cough thru either central or peripheral mech, or a combo of the 2.

• Guaifenesin and codeine (Cheratussin AC)- schedule V
• dextromethorphan

• Cough:  10 ml PO q 4-6h prn
• Dosage forms: 10/100/ 5 mL
• 10 codeine, 100 guaifenesin, in every 5 mL
• Max daily dose (MDD) required on Rx
• Dose should be decreased for renally impaired
• Does have alcohol in it

• Camphor
• menthol
• eucalyptus oil
• Benzonatate (Tessalon)

by anesthetizing the stretch receptors located in the respiratory passages & lungs

• Severe hypersensitivity reactions (including bronchospasm, laryngospasm and       cardiovascular collapse) have been reported
• Possibly related to local anesthesia from sucking or chewing the capsule instead of swallowing it

• Inhibit the cough center in the brain
• Exact mechanism not well understood

• Anesthetize local nerve endings
• Act as demulcents (soothing agents)

• Lower pharynx, larynx, trachea & small airways of respiratory system are       innervated by vagus & glossopharyngeal nerves
• Stimulation of sensory receptors of these nerves leads to cough
• Irritant leads to cough
• Receptors relay info to cough center in brain (medulla)
• A reflex motor response occurs; results in contraction of muscle to close glottis & muscles of expiration
• Leads to an increase in intrathoracic pressure, followed by relaxation of the glottis
• This results in rapid expulsion of air

cough

• Onset occurs in 15–30 minutes. Peak antitussive effects within 1–4 hours.
• Rapidly distributed into various body tissues.
• Distributed into milk. Readily crosses the placenta.
• Metabolized in liver, principally by CYP3A4, to O-demethylated morphine, the active       metabolite.
• genetic differences in drug metabolism affect drug response
• Excreted mainly in urine
• Half-life: about 2.5–3 hours

• Onset of action is 15-30 minutes·
• Duration is 3-6 hours

• Used topically  (vapors inhaled)
• inhaled through a vaporizer

• Drowsiness
• nausea
• dizziness

• Sedation
• HA
• dizziness
• Can numb mouth
• Warn patients:  Do not chew or dissolve in the mouth when used as an antitussive
• Why? temporary, potentially life-threatening local anesthesia of the oral mucosa, choking, or severe hypersensitivity reactions could occur.

• Lightheadedness
• nausea
• sedation
• constipation

• Dextromethorphan and MAOI inhibitors (selegiline, tranylcypromine, phenelzine,       isocarbozazid) use within 14 days;
• Why? MAOI directly inhibit this enzyme, increases the amount in the synapse-increased  risk of serotonin syndrome- confusion, uncoordination, agitation
• Ppl  are abusing unexpected OTC & rx meds
• -dextromethorphan taken in high doses can create euphoria
• OTC  cough & cold med in children:
• -lifestyle modifications are 1st line of tx: humidifiers, saline, & nose suctioner
• -encourage parents to avoid using vicks, can make it worse

facilitate the removal of mucous from the respiratory tract

Guaifenesin (Robitussin) (Mucinex)

chest congestion

Increases volume & decreases viscosity of respiratory secretions, resulting in increased flow & clearance of irritants  (“loosens” phlegm)

half-life is 1 hr

• 10/100/5ml
• contains alcohol
• 20 mg codeine PO q4-6h prn.
• Adjust dose amount in renal impairment

20 mg= 10 mL

• Direct alpha-1 agonists
• Indirect alpha-1 agonists

• Phenylephrine (Dimetapp)- not very effective be it is poorly absorbed
• Oxymetazolone
• Naphazoline

• Pseudoephedrine
• Ephedrine

all nasal decongestants are vasoconstrictors

• nasal congestion; reduces "stuffiness"
• ocular congestion
• -temporary relief of conjunctival congestion, itching, & minor irritation
• -used alone or in fixed combo c/ antihistamines &/or astringents

Visine

Naphcon, Visine A

• orally, topically, and ophthalmics
• Pseudoephedrine: (oral) onset c/in 30 mins
• Nasal decongestion may persist for 8 hours following oral administration of 60 mg and up to 12 hours following 120 mg of the drug in extended-release capsules.
• Presumed to cross the placenta
• About 0.5% of an oral dose is distributed into milk over 24 hours.
• Incompletely metabolized in the liver·
• Excreted in urine·
• Half-life is 9-16 hours; decreased excretion in alkaline urine

• Inhaled: Rhinitis medicamentosa- rebound congestion
• What can you do it pt has this? Taper them off it
• CNS stimulation ; Anxiety, agitation, insomnia; take it during the day(Pseudophedrine)
• Dizziness
• Palpitations
• increased blood pressure
• urinary retention
• Topical agents may cause stinging, burning & dryness

• Severe HTN
• CAD
• MAOI use c/in 14 days (may lead to hypertensive crisis)

• Combat Methamphetamine Epidemic Act of 2005
• The act bans OTC sales of cold meds that contain the ingredient pseudoephedrine

antagonize the allergic responses & other effects mediated by histamine

• Diphenhydramine (Benadryl)
• Chlorpheniramine (Chlor-Trimeton)
• Brompheniramine      
• Promethazine (Phenergan)
• Hydroxyzine (Vistaril)
• Meclizine (Antivert) (Dramamine)
• Clemastine (OTC & Rx) (Tavist Allergy)
• Cyproheptadine (Rx) (Periactin)- DC'd
• (Die C B Penis c/ Horrible and Mighty Condylomata & Chlamydia)

• (Claritin)(Alavert) Loratadine - 10 mg·
• (Zyrtec)Cetirizine
• (Allegra) Fexofenadine
• (Astelin) Azelastine (nasal)
• (Optivar) Azelastine (ophthalmic)
• (Clarinex) Desloratadine
• (Xyzal) Levocetirizine
• (Patanase) Olopatadine (nasal)

• Moderate to severe allergic rxns: 25-50 mg q 2-4 hrs.
• not to exceed 400 mg/day

10 mg

5-10 mg PO once daily

• 60 mg PO 2x daily OR
• 180 mg PO once daily

allergic rxns

• to reduce gastric acid
• Cimetidine (Tagamet)
• Ranitidine (Zantac)
• Famotidine (Pepcid)

mast cells

• Bronchoconstriction
• Vasodilation
• Nerve sensitization

• Antihistamines competitively antagonize histamine at the H1 receptor; altering the       immune response to an allergen:  (opposite of:)
• -Bronchoconstriction
• -Vasodilation
• -Nerve sensitization

inflammation of the mucous membrane

• Due to mucous membrane exposure to an inhaled allergen; results in a specific       response mediated by immunoglobulin E (IgE)
• Response is characterized by sneezing, itchy, runny nose, & often nasal congestion & postnasal drip. Itchy eyes, ears and throat frequently accompany allergic rhinitis.

• Allergic  symptoms
• Allergic reactions
• Urticaria
• Motion sickness prevention
• Nausea

• allergen avoidance
• pharmacotherapy to prevent or treat symptoms
• specific immunotherapy
• Antihistamines are more effective in preventing, rather than reversing, the actions of histamine.
• Reversal of symptoms is probably due, in part, to the anticholinergic effects of the drugs.

• Sneezing,runny nose, itching, conjunctivitis
• For seasonal. Begin tx before allergen exposure

Conjunctivitis

Sneezing, runny nose, nasal itchiness

• Well absorbed
• Large volume of distribution
• Metabolized by liver
• Older agents are lipid soluble

• Anticholinergic (drying) effects: (first generation)
• Dry mouth
• Difficulty urinating
• Constipation
• Changes in vision
• Drowsiness (less of a problem with second generation)

patients <6 and >65 years old, CNS depressant use, increased intraocular pressure, hepatic or renal disease, hypertension, asthma, COPD, peptic ulcer disease, BPH, hyperthyroidism