Download PowerPoint_Chapter11

Chapter 11
Drugs for Eyes, Ears, Nose,
and Throat
© Paradigm Publishing, Inc.
2
Chapter 11
Topics
• Anatomy and Physiology of the Eyes,
Ears, Nose, and Throat
• Glaucoma
• Eye Infections
• Eye Allergies and Chronic Dry Eye
• Retinopathy and Macular Degeneration
• Ear Infections
• Rhinitis, Seasonal Allergies, and Colds
• Herbal and Alternative Therapies
© Paradigm Publishing, Inc.
3
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
The Sensory System
• Includes organs that produce the five senses: vision,
hearing, smell, taste, and touch
• Eyes and ears are associated with drug therapy because
they are sites of administration for medication
Eyes
• Sense light and produce vision
• Light enters the eye through the pupil and is focused by
the lens (located behind the pupil)
• Iris (surrounds the pupil) determines eye color and the
sclera is the outer coating of the eyeball (white of eye)
© Paradigm Publishing, Inc.
4
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Anatomy of the Eye
Drugs are used to treat problems in the conjunctiva,
anterior chamber, retina, and macula
© Paradigm Publishing, Inc.
5
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Sight
• Begins with light that travels through the lens to the back
of the eye, the retina
• In the retina, photoreceptor cells detect light and color
• These rod- and cone-shaped cells send signals via the optic
nerve to the brain which perceives and interprets sight
 Rod cells are responsible for night vision and cone cells
are responsible for day vision
• Inside the macula is the focal point (fovea centralis) on the
retina where light is concentrated for vision
 This part of the retina is rich in cone cells
© Paradigm Publishing, Inc.
6
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Other Parts of the Eyes Relevant to Drug Therapy
• Cornea
 Covers the anterior chamber
• Anterior chamber
 Holds aqueous humor, a fluid that lubricates and
protects the lens
• Vitreous humor
 Is the fluid inside the eye, behind the lens
• Ciliary muscle
 Holds the lens in place
• Conjunctiva
 Forms the socket that hold the eye in place
© Paradigm Publishing, Inc.
7
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Anatomy of the Retina
© Paradigm Publishing, Inc.
8
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Ears and Sound
• Ears sense sound waves and produce hearing; have three
parts: external, middle, and inner
• External ear captures sound waves that go through the
auditory canal to the tympanic membrane (eardrum)
 Cerumen (earwax) produced inside the auditory canal
• Eardrum
 Separates the middle ear and external ear
 Vibrates in response to sound waves, causing the
three bones of the middle ear to move
• One of the bones taps on the oval window (the entrance
to inner ear)
© Paradigm Publishing, Inc.
9
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Anatomy of the External, Middle, and Inner Ear
© Paradigm Publishing, Inc.
10
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Ears and Sound (continued)
• Eustachian tube connects the middle ear to the throat;
fluid drains when atmospheric air pressure changes
• Inner ear includes the semicircular canals and the cochlea
• Fluid in the cochlea responds to tapping on oval window
and produces pressure waves
• Waves flow through the organ of Corti (spiral-shaped),
which is lined with tiny sensory hairs
• Vibrations in the hairs send signals to the brain, where
sound is perceived and interpreted
© Paradigm Publishing, Inc.
11
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Sound Movement through the Inner Ear
Strong waves from loud noises break off tiny hairs in the
cochlea, causing hearing loss
© Paradigm Publishing, Inc.
12
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
URT
• Includes the nasal passages, sinuses, back of the throat,
pharynx (Adam’s apple), and larynx (voice box)
• Includes structures above the trachea (opening to the
lungs)
 Lower respiratory tract includes structures below the
trachea
• Chemoreceptors in the nose produce the sense of smell
• Sinuses and throat are common sites for viral and bacterial
infections
• A cold and allergies cause symptoms affecting the URT,
such as coughing, sinus pain, postnasal drainage, and
congestion
© Paradigm Publishing, Inc.
13
Anatomy and Physiology of the Eyes, Ears, Nose, and Throat
Upper Respiratory Tract
© Paradigm Publishing, Inc.
14
Glaucoma
About Glaucoma
• Is a condition in which abnormally high intraocular
pressure pushes on the optic nerve and damages it
• Can lead to blindness unless treated
• Caused by overproduction of aqueous humor or blockage
of its outflow from the anterior chamber
• Open-angle glaucoma
 Is a slowly progressing, chronic condition managed with
medication alone
• Narrow-angle glaucoma
 Is an acute condition that comes on quickly and is
resolved with surgery followed by drugs
© Paradigm Publishing, Inc.
15
Glaucoma
Normal Aqueous Humor Flow and Glaucoma
© Paradigm Publishing, Inc.
16
Glaucoma
Administering Eyedrops
• Most eye conditions, especially glaucoma, are treated with
topical agents administered directly in the eyes
• Ophthalmic drops and the applicator tip must remain
sterile so as not to cause infection in the eye
• To instill eyedrops, take out contact lenses if wearing them
 Pull the lower eyelid downward and gently squeeze
container for drops to fall into the eye
 Applicator tip must not touch the eye, eyelid,
eyelashes, or fingers
© Paradigm Publishing, Inc.
17
Glaucoma
Instilling
Eyedrops
• Most eye drops
are solutions
• If suspensions,
shake well
before using
© Paradigm Publishing, Inc.
18
Glaucoma
Drugs for Glaucoma
• Topical beta blockers, alpha receptor agonists,
sympathomimetics, miotics, carbonic anhydrase inhibitors,
and prostaglandin agonists are given as eyedrops for
glaucoma (see Table 11.1)
• Beta blockers are first-line therapy
• Mechanism of Action (ophthalmic glaucoma agents):
reduce aqueous humor production
• Mechanism of Action (miotic agents): constrict the pupil
slightly by contracting the ciliary muscle
 Contraction enhances aqueous humor outflow
© Paradigm Publishing, Inc.
19
Glaucoma
Drugs for Glaucoma (continued)
• Dosage Form (most): ophthalmic solution (eyedrops)
• Dosage Forms (exceptions): acetazolamide (Diamox) and
methazolamide are oral
• Side Effects (common): mild stinging, tearing, itchy eyes,
and dry eyes
• Side Effects (severe): beta blockers can cause systemic
effects if enough is absorbed into the bloodstream
 Slowed heartbeat, heart problems, insomnia, dizziness,
vertigo, headaches, tiredness, and difficulty breathing
© Paradigm Publishing, Inc.
20
Glaucoma
Drugs for Glaucoma: Cautions
• If heart or thyroid problems, discuss drug therapy
(especially beta blockers ) with prescribers
• Prostaglandin agonists can cause the iris of the eye to
brown
• Oral dosage forms of carbonic anhydrase have several drug
interactions and cautions
 Discuss with prescriber if have kidney or liver problems,
diabetes, gout, or asthma
• Apply warning label that these products are to be used in
the eyes only
© Paradigm Publishing, Inc.
21
Eye Infections
Conjunctivitis and CMV
• Conjunctivitis (“pink eye”)
 Is inflammation caused by bacteria in the mucous
membranes surrounding the eye
 Symptoms include redness of the sclera and insides of
the eyelids, itching, pain, tearing, and release of matter
 Treat with antibiotics
• CMV
 Is a viral infection of the inner eye that occurs almost
entirely in patients with HIV or AIDS
 Can lead to blindness
 Treatment involves chronic suppression with antivirals
© Paradigm Publishing, Inc.
22
Eye Infections
Herpes Viruses
• Herpes zoster
 Is a virus that causes chickenpox and shingles
• Herpes simplex
 Is a virus that causes cold sores
• Cause of various problems with the eyes and eyelids
• Symptoms include eye pain, redness, cornea cloudiness,
tearing, decreased vision, and aversion to bright light
• Can cause blindness in serious herpetic viral infections
• Treat with topical antiviral agents
© Paradigm Publishing, Inc.
23
Eye Infections
Administering Eye Ointment
• Applying eye ointment
 Pull the lower eyelid downward
 Squeeze a continuous ribbon (half-inch) of ointment
along the space between the eyeball and lower lid
 Close the eye for a few minutes to allow ointment to
liquefy (vision may be blurry for a few minutes)
 Gently wipe away excess ointment
• Ointments must remain sterile and the applicator tip
should not touch the eye or eyelid
• Remove contact lenses before applying ointment
© Paradigm Publishing, Inc.
24
Glaucoma
Applying Eye
Ointment
Learning to apply
eye ointment may
take practice
© Paradigm Publishing, Inc.
25
Your Turn
Question 1: A patient is diagnosed with glaucoma. What drug
therapy is the physician likely to order?
Answer: Beta blockers are first-line therapy for glaucoma and
are used most frequently.
Question 2: A patient has a new prescription for an antiviral
medication that is an ointment. How will she apply the
ointment?
Answer: The patient will pull the lower eyelid downward and
squeeze a continuous ribbon (half-inch) of ointment along
the space between the eyeball and lower lid. Then she will
close the eye for a few minutes. She can gently wipe away
any excess ointment.
© Paradigm Publishing, Inc.
26
Eye Infections
Drugs for Eye Infections
• Anti-infective agents (see Table 11.2)
 Include antibiotics and antiviral medications
 Chosen based on the type of infection and suspected
organism
Topicals are used unless the infection is systemic
• Ophthalmic corticosteroids (see Table 11.3)
 Are useful for calming inflammation caused by an
infection
 Are used to reduce pain, redness, and irritation, but do
not cure the infection
© Paradigm Publishing, Inc.
27
Eye Infections
Drugs for Eye Infections (continued)
• Routes (anti-infectives): most are ophthalmic; antivirals
class are IV, oral, intravitreal, and ophthalmic
• Routes (ophthalmic corticosteroids): all are ophthalmic
except triamcinolone (Triesence, Trivaris) is intravitreal
• Side Effects: few and mild
• Cautions: many people have allergies to anti-infectives
• Apply warning label on all ophthalmic products so that the
patient knows they are intended for use in the eyes only
and suspensions should have a “shake well” label
© Paradigm Publishing, Inc.
28
Eye Allergies and Chronic Dry Eye
Drugs for Eye Allergies and Chronic Dry Eye
• Eye Allergies
 Are the exposure to allergens (pollen, dust, smoke, and
pollution) that trigger symptoms
 Symptoms include redness, itching, tearing, and
possible conjunctivitis
 Treatment includes topical antihistamines, NSAIDs,
decongestants, mast cell stabilizers (see Table 11.4)
Reduce redness and inflammation
Ophthalmic NSAIDs also used for pain associated
with cataract surgery
© Paradigm Publishing, Inc.
29
Eye Allergies and Chronic Dry Eye
Drugs for Eye Allergies and Chronic Dry Eye
(continued)
• Chronic dry eye
 Is the inability to produce sufficient tears and
lubrication for the eye
 Is a side effect of drugs with anticholinergic effects
 Treat with normal saline drops or artificial tears first
 Use cyclosporine if serious, which directly reduces
immune activity within the eye
• Side Effects (ophthalmic agents): mild stinging or burning
• Antihistamines and anti-inflammatories take a few days to
work; cyclosporine and mast cell stabilizers take 4 weeks
© Paradigm Publishing, Inc.
30
Retinopathy and Macular Degeneration
Retinopathy
• Is the destruction of the retina
• Caused by many conditions; the most common is diabetes
• Diabetic retinopathy
 Tiny blood vessels supplying the retina with blood are
damaged and minute hemorrhaging occurs
 Is a leading cause of blindness in the U.S.
 Prevent through proper treatment and control of blood
glucose levels
• Laser treatments for early retinopathy can halt vision loss
• Annual eye exams are important for preserving eyesight
© Paradigm Publishing, Inc.
31
Retinopathy and Macular Degeneration
Macular Degeneration
• Is a painless condition that is associated with age and can
go undetected until vision is significantly affected
• Macula
 Is responsible for central vision
• Dry macular degeneration
 Is tissue breakdown in the macula occurring with age
 Symptoms are blurry vision and more light for reading
• Wet macular degeneration
 Is the breakdown of tissue occurring rapidly from fast
blood vessel growth and rupture
 Not associated with age; straight lines appear wavy
© Paradigm Publishing, Inc.
32
Ear Infections
External and Middle Ear Infections
• External ear infection (otitis externa)
 Is an infection of the ear canal; common in swimmers
 Bacteria or fungi thrive in moist environments like
earwax
• Middle ear infections (otitis media)
 Is most common in children; fluid from the middle ear
does not drain well
 Most are viral and clear on their own
 Symptoms are ear pain, jaw pain, sinus pain, itching,
and fever
• Treatment for ear infections is antibiotics
© Paradigm Publishing, Inc.
33
Ear Infections
Administering Eardrops
• Are topical medications effective only for certain
infections, such as otitis externa
• Middle and inner ear infections require oral drug therapy
• Routes: mostly suspensions; also solutions
 If tubes in ear, use suspension only
• Important to keep otic preparations sterile; do not touch
tip of applicator to ears or with fingers
• Ophthalmic products can be used in the ear
• Do not use otic drops in the eyes; painful
© Paradigm Publishing, Inc.
34
Dosage Forms and Routes of Administration
Otic Administration
• Turn the head
horizontally
• Pull on earlobe
and allow
drops to fall
into ear canal
• Remain lying
down to allow
liquid to coat
the ear canal
Pull ear up
and out for
adults
© Paradigm Publishing, Inc.
Pull ear down
and back
if under age 3
35
Ear Infections
Drugs for Ear Infections
• Indications (otic antibiotic preparations): bacterial
infections of external ear or middle ear infection if
eardrum rupture or ear tubes are present (see Table 11.5)
• Indication (drying agents): prevention of external ear
infections, especially for regular swimmers
• Indication (earwax removers): cerumen impaction
• Indication (topical otic analgesics): severe ear pain
associated with infection (see Table 11.6)
• Side Effects (all otic products; rare): allergic reactions
© Paradigm Publishing, Inc.
36
Ear Infections
Ototoxicity
• Is damage to the ear from chemical or drug exposure
• Can cause hearing loss due to some drugs, such as
aminoglycosides
 Usually temporary if caught early
• Symptoms begin as ringing in the ears (tinnitus) and
progress to noticeable hearing loss
© Paradigm Publishing, Inc.
37
Ear Infections
Drugs that Can Cause Ototoxicity
• Aminoglycosides
• Furosemide
• Aspirin and salicylates
• Neomycin
• Benzodiazepines
• NSAIDs
• Calcium-channel
blockers
• Quinine
• Cisplatin and some
chemotherapy agents
• Erythromycin and
macrolides
• Some HIV antiviral
agents
• Tricyclic antidepressants
• Valproic acid
© Paradigm Publishing, Inc.
38
Rhinitis, Seasonal Allergies, and Colds
Common Conditions of the URT
• Includes rhinitis (runny nose), sinus congestion,
pharyngitis (sore throat), laryngitis (loss of voice), and
epistaxis (nose bleeding)
• Seasonal allergies or the common cold
 Cause runny nose and nasal congestion
Allergies
• Symptoms include watery, itchy eyes; sneezing; runny
nose; and sinus congestion
• Common allergens include dust, pollen, pet dander, and
cigarette smoke
© Paradigm Publishing, Inc.
39
Rhinitis, Seasonal Allergies, and Colds
Allergies (continued)
• Cells in the respiratory tract release histamine and
other inflammatory mediators
• Histamine dilates arterioles, allowing blood
contents to leak into the local area
 WBCs (fight disease and foreign allergens)
move to the affected area
 Causes swelling, mucus production, and
soreness
• Treatment involves avoiding allergens and use of
anti-inflammatory medications
 Antihistamines and decongestants (for relief)
© Paradigm Publishing, Inc.
40
Rhinitis, Seasonal Allergies, and Colds
The Common Cold
• Can elicit a similar response as allergies
• Has no cure because too many virus strains quickly
mutate
• Treatment is symptom relief
 Use antihistamines, decongestants, cough
suppressants, and mucolytics
Help with runny nose, stuffy nose,
coughing, and chest congestion
© Paradigm Publishing, Inc.
41
Rhinitis, Seasonal Allergies, and Colds
Drugs for Rhinitis, Seasonal Allergies, and
Colds
• Treatment for rhinitis and nasal allergies
 Are many of the same drugs for common cold
symptoms
• Indications (antihistamines and nasal
corticosteroids): runny nose, watery/itchy eyes,
and sneezing
• Indications (decongestants): nasal congestion from
allergies and cold symptoms of stuffy nose and
sinus pain
© Paradigm Publishing, Inc.
42
Rhinitis, Seasonal Allergies, and Colds
Antihistamines
• Indications
 Symptomatic relief of excess nasal secretions,
itching, sneezing, coughing
 Itching and redness from allergic reactions
(such as hives and rashes)
 Cause sedation which is used for mild insomnia,
relaxation before anesthesia
Active ingredient in most OTC sleep aids
First-generation more sedation than second
 Motion sickness and Parkinson’s disease
© Paradigm Publishing, Inc.
43
Rhinitis, Seasonal Allergies, and Colds
Antihistamines (continued)
• Mechanism of Action: block histamine (H1)
receptors, reducing capillary dilation and leakage
• Routes: all are oral; diphenhydramine (Benadryl) is
also IM and IV
• Dosage: vary widely based on patient age, dosage
form, reason for use (see Table 11.8)
• Side Effects (common): drowsiness (firstgeneration), dry mouth, and urinary retention
© Paradigm Publishing, Inc.
44
Rhinitis, Seasonal Allergies, and Colds
Antihistamines (continued)
• Side Effects (severe)
 Do not take with medications that cause drowsiness
 Do not take alcohol
 Do not take with urination problems
 May cause excitation (not drowsiness) in children
• Cautions
 Talk to prescriber if high blood pressure or heart
problems
 Do not give to infants or take if breast-feeding
 Do not take if have glaucoma or if using MAOIs
© Paradigm Publishing, Inc.
45
Rhinitis, Seasonal Allergies, and Colds
Decongestants
• Indications: sinus congestions and pain caused by
common cold, infections, and allergies
• Mechanism of Action: stimulate adrenergic receptors
which constricts blood vessels and reduces swelling
• Dosage: varies based on patient age, dosage form, and
reason for use
• Side Effects (common): headache, dizziness, lightheadedness, insomnia, nervousness, and nausea
• Side Effects (serious): increased blood pressure and
fast or irregular heartbeat
© Paradigm Publishing, Inc.
46
Rhinitis, Seasonal Allergies, and Colds
Decongestants (continued)
• Cautions
 Can cause rebound swelling if used for more than 3
days
 May worsen congestion after stopping product
use
Lasts a few days
Patients may use product longer than needed
 Some are OTC but restricted, including
pseudoephedrine
Limits on quantities purchased and must be 18
years of age
© Paradigm Publishing, Inc.
47
Rhinitis, Seasonal Allergies, and Colds
Cough Suppressants
• Indication: excessive and nonproductive (dry, hacking)
coughing
• Mechanism of Action: Depress cough reflex in cough
center of the medulla in the brain
• Side Effects: drowsiness, dizziness, and stomach upset;
do not take with alcohol
• Cautions: Codeine-derivative cough suppressants are
OTC but restricted
 Limits on quantities purchased
© Paradigm Publishing, Inc.
48
Rhinitis, Seasonal Allergies, and Colds
Expectorants (Mucolytic Agents)
• Indication: productive (wet, mucus-producing)
cough
• Mechanism of Action: liquefy respiratory
secretions to allow them to be cleared easily
• Dosage: varies widely based on patient age,
dosage form, and reason for use (see Table 11.10)
• Side Effects: Stomach upset and headache but are
usually rare and mild
© Paradigm Publishing, Inc.
49
Your Turn
Question 1: What is the difference between prescribing
ophthalmic drops and otic drops for ear and eye infections?
Answer: Ophthalmic drops can be used in both the ear and
eye, but otic drops can only be used in the eyes.
Question 2: Why is there no cure for the common cold?
Answer: The common cold has no cure because there are too
many virus strains that quickly mutate.
© Paradigm Publishing, Inc.
50
Rhinitis, Seasonal Allergies, and Colds
Topical Nasal Corticosteroids
• Indications: Nasal allergy symptoms localized to
the URT (i.e., nasal passages)
• Mechanism of Action: reduces inflammation and
allergy symptoms
• Route: intranasal
• Administration
 Patient is upright, head tilted slightly forward
 Insert sprayer tip into nostril, then depress
applicator to deliver metered dose
 Breathe gently and slowly when depressing
© Paradigm Publishing, Inc.
51
Rhinitis, Seasonal Allergies, and Colds
Topical Nasal Corticosteroids (continued)
• Side Effects (common): cough, sore throat,
headache, runny nose, and nosebleeds, especially
in children
• Cautions
 Shake product well before administration
 Prime spray application bottle when new and
when it has not been used for a while
Pump the sprayer a few times until an even
amount of spray exists the applicator
© Paradigm Publishing, Inc.
52
Herbal and Alternative Therapies
• Echinacea, zinc, and vitamin C
 Are taken to boost immune function and fight off
cold and flu viruses
 Standardized regimens have not been proven
• Vitamins A (beta carotene), C, E, and zinc
 May slow disease progression of age-related macular
degeneration
 Ocuvite (brand-name combination product )
Does not cure or prevent macular degeneration
Do not take if smoke
Do not take if have high risk of certain cancers
© Paradigm Publishing, Inc.
53
Summary
• Topical beta blockers, alpha agonists, sympathomimetics,
miotics, carbonic anhydrase inhibitors, and prostaglandin
agonists are given as ophthalmic drops for glaucoma
• Numerous antibiotics and antiviral medications are
administered as eyedrops and ointments
• Eardrops are used most often for external ear infections
but can be used for inner ear infections
• Antihistamines, decongestants, cough suppressants, and
expectorants are used to for symptoms of colds,
infections, and allergies
© Paradigm Publishing, Inc.
54