pharm Ch 29 Drug therapy for Eye problems

The most common problems affecting the eye that can be treated or controlled by drug therapy are

inflammation, infection and glaucoma.

Glaucoma

Is a condition of increased IOP caused by an increase in the amount of aqueous humor.

both eyes can have the problem, or it may affect only one eye.

Does drug therapy for Glaucoma cure the problem?

no it only controls it

If intraocular pressure (IOP) is too low

the eyeball is soft and collapses, preventing light from striking the photoreceptors in the back of the eye.

if intraocular pressure (IOP) is to high

it compresses blood vessels in the eye, reducing blood flow ad oxygen delivery to the photoreceptors. Without enough oxygen, the photoreceptors and the optic nerve die, and sight is lost permanently.

(IOP) has to be just right

Constriction of the pupil is

miosis

small word, small pupil size

dilation of the pupil is

mydriasis

larger word, larger pupil size

why is Keeping the IOP within the normal range (10-20mm Hg) important?

important in order to maintain vision

what is the Most common type of Glaucoma?

Primary open angle glaucoma

POAG

painless, no early symptoms; peripheral vision (tunnel) lost first

Eye drops

are thin, sterile, liquid drugs that are squeezed as a small drop or drops from a small container.

Eye onitments

are thick, greasy drugs that stay in contact with the eye surface longer than drops. They can deliver a high concentration of drug and blur vision for minutes to hours after instillation.

The intended responses for all drug therapies for glaucoma are

IOP is reduced to the normal range

There is no further loss of sight

Before giving eye drops:

check the order to see which eye is receiving the drug

avoid the use of the latin terms for right eye (OD) left eye (OS) and both eyes (OU)

WASH YOUR HANDS

Always check the strength prescribed with that of the drug you have on hand to be sure that you are giving the correct dose.

Check to be sure that a tube of ointment is for ophthalmic (eye) use

Check if you need to administer any other drops

instill two or more drug sets at 10-min intervals

Assess for redness, drainage, open areas

remove contacts

After giving eye drops..

Apply gentle pressure to the punctum in the corner of the eye for about 1 minute (This action is called punctal occlusion and reducese systemic absorption of the drug)

Keep the eye closed for about 1 minute after instilling the drug

Teach patient

use exactly as prescribed

sudden head movement can cause the tip of the bottle to scratch the eye

DO NOT SHARE EYE OINTMENT

dont drive

report any new symptoms (general or specific to the eye) to their prescriber as soon as possible.

older adults may have more difficult self- administering eye drops because of physical limitations, adaptive devices are available that hold the bottle of eye drops and help keep the eyelids open. When the device is placed around the eye, the top of the bottle lines up directly over the center of the eye. The patient then only has to trigger the right number of drops. Although this method does not place the drops in a lid pocket, it is acceptable.

Teach patients the steps in box 29-1 for correctly instilling drops into one or both eyes.

page 460

Using saline eye drops for practice, demonstrate the steps to patients and have patients demonstrate them back to you. if a patient has physical problems or is confused and cannot instill the eye drops, teach a family member, friend, or neighbor how to do this correctly. teach patients how to use punctal occlusion by applying pressure over the punctum immediately after instilling the drops. This action keeps the drug on the eye longer and helps to prevent systemic effects

If infants or young children need eye drugs...

demonstrate drug instillation to the parent or guardian and teach them to obtain the assistance of another adult.

These drugs should be avoided during the first trimester of?

pregnancy and used with caution during the later 6 months of pregnancy. Breastfeeding is not recommended during glaucoma therapy.

drugs for glaucoma

improve the reabsorption of aqueous humor and or reduce the amount that is made.

these actions restore good blood flow inside the eye and keep the remaining photoreceptors of the optic nerve healthy.

Most glaucoma drugs are administered as?

eye drops

for sudden- onset glaucoma (acute closed-angle glaucoma) systemic drugs may be used.

The five classes of drugs to treat glaucoma are

prostoglandin agonists

beta blockers

alpha adrenergic agonists

chollinergic drugs

carbonic anhydrase inhibitors

The prostaglandin agonists are very effective they are used only once a day and seem to what?

have fewer systemic side effects than other drugs.

Use aseptic technique when instilling eye drugs because the eyes can easily..

become infected

Apply only ointments that are labeled

"for ophthalmic use" in the eye

Place eye drops or eye ointments only in the

affected eye

if both eyes are to be treated and one eye is infected,

use a separate bottle or tube for each eye

place the drops or ointment into a pocket created by..

gently pulling the lower lid downward.

Never touch any part of the patient's eye with the

tip of the bottle or tube

Drugs administered as eye drops can enter the

blood and cause systemic effects

When instilling eye drops that can have systemic effects

apply gentle pressure to the corner of the eye nearest the nose ( the inner canthus where the drainage ducts are located) for 1 to 2 minutes after instilling the drops.

Teach the patient to use eye drops or ointments exactly as directed and to...

never use more drug than prescribed.

Glaucoma can occur at any age and

can affect one or both eyes

untreated glaucoma leads to

blindness

The goal of glaucoma therapy is to keep the IOP within

normal range and prevent loss of photoreceptors.

Most drugs for glaucoma come in different strengths be sure to

check the strength of the drug that you have on hand with that of the prescription to prevent overdosing or underdosing

Adrenergic agonists cause the pupils to

dilate and the eye to be more sensitive to light. Urge patients to wear dark glasses or a hat with a brim in bright conditions.

Beta blockers and cholinergic drugs make the pupil smaller even in

low light conditions. teach patients to be more cautious in dim lighting to avoid falls and to use more light to read or do close work.

Beta blockers and cholinergic drugs, if absorbed systemically, can

slow the heart rate and lower blood pressure and cause asthma. Be sure to warn patients about these side effects and tell them to notify their prescriber if symptoms appear or worsen.

Warn patients with diabetes that beta blockers can mask

the symptoms of hypoglycemia. Blood glucose levels may need to be check more often.

Over time the prostaglandin agonist eye drops change the

color of the iris to brown, darken the eyelids and increase the number and length of eyelashes.

Which brand name drugs belong to the prostaglandin agonist class? select all that apply

lumigan

travatan

xalatan

Which adverse effect can occur as result of excessive use of prostaglandin agonists?

increasaed body hair

For which eye-drop-delivered drug is it most important that the corneal surface be intact?

travoprost (travatan)

Which patient problem is a contraindication for use of the beta-adrenergic antagonist drugs?

Asthma

Which drug for glaucoma must be avoided for patients who have an allergy to sulfa drugs?

Dorzolamide (trusopt)

You are teaching a family member to apply eye drops before a patients surgery. into which exact area do you instruct the drops to be instilled?

the pocket created by pulling down the lower lid

Which patient response is most important to check after administering an adrenergic agonist for control of glaucoma?

heart rate and ryhtm

The emergency department (ED) nurse is admitting a patient with glaucoma. What type of glaucoma is considered a sudden onset type?

Acute closed-angle

Acute closed-angle glaucoma is sudden onset glaucoma. Primary open-angle glaucoma is a chronic problem where aqueous humor is not reabsorbed well because of thickening of blood vessels in the trabecular meshwork. It is the most common type of glaucoma and has no pain or other warning signs. Acute open-angle glaucoma is not an actual condition. Secondary glaucoma is caused by another problem in the eye. Usually when the other problem is treated successfully, glaucoma is reduced or may go away completely.

The nurse is preparing to administer two different types of eye drops to a patient. How many minutes apart should these eye drops be instilled into the same eye?

10

The nurse is preparing to administer eye ointment to a patient. Which routine action done before the instillation of the ointment best reduces the chance of instilling contaminated medication into a patient's eyes?

Squeezing a small amount out of ointment onto a tissue

For ointments, after removing the cap from the ointment tube, squeeze a small amount out onto a tissue (without touching the tip of the tube or letting it come into contact with the tissue) and discard this ointment. This action reduces the chance of instilling contaminated ointment into the patient's eye. Check to be sure that a tube of ointment is for ophthalmic (eye) use. Some drugs for the eye are also available as regular topical ointments, but these contain larger particles that should not be placed in the eye. Instruct patients not to share the eye ointment with anyone else to prevent spreading eye infections from one person to another. Wipe any excess drug from the patient's skin to prevent systemic side effects. The tip of the ointment tube should not come into contact with the tissue. Using a separate ointment tube is only necessary if one eye is infected and the other is not.

You are preparing to administer timolol (Betimol) eye drops. Which is the best technique to prevent systemic side effects in the patient?

Performing punctal occlusion

Punctal occlusion keeps the drug on the eye longer and helps to prevent systemic effects. This action involves applying pressure over the punctum immediately after instilling the drops. Blinking the eye will not prevent systemic side effects. With beta blockers such as timolol, excessive fluid to intact skin would not likely cause systemic side effects. Forming a small pocket in the eye by pulling out the lower lid is the best way to administer eye drops but it does not promote or prevent systemic side effects.

A patient reports a sudden decrease in vision after the installation of eye drops. After determining that the vision change is not due to blurriness from the installation process, what should you tell the patient to do?

Go to the emergency department

A patient has been prescribed travoprost (Travatan). Which instruction, particular to travoprost, should you include in patient teaching?

This drug may cause your eye color to darken

Travoprost (Travatan) is a prostaglandin agonist. One of the most common side effect of this drug is a permanent change in the iris color from lighter colors to brown. Other side effects include eye itching, eye redness, thickening and lengthening of the eyelashes, and darkening of the skin on the eyelids. If only one eye has glaucoma, the color and lash changes will occur only in that eye

The nurse is administering eye drops to a patient. The nurse knows that what type of glaucoma eye medication carries has the greatest risk of systemic reactions when coming into contact with the patient's skin?

Carbachol (Carboptic)

Carbachol (Carboptic) is a cholinergic drug. If excess amounts of a drug of this type are present on the patient's skin, wipe it off immediately to prevent systemic side effects because these drugs can be absorbed through the skin.

Adverse effects related to systemic absorption of prostaglandin agonists such as travoprost are rare. Adrenergic agonists such as brimonidine can have systemic effects, but these symptoms only occur when the drug is overused. Adrenergic agonists such as apraclonidine can have systemic effects, but usually these symptoms only occur when the drug is overused.

What drug category offers an oral form medication to control glaucoma?

Carbonic anhydrase inhibitor

The nurse is giving a glaucoma medication to a patient. For which medication is it most important for the nurse to check whether the patient is taking a monoamine oxidase (MAO) inhibitor?

Apraclonidine (Iopidine)

Apraclonidine (Iopidine) is an adrenergic-agonist eye medication. Adrenergic-agonist eye drops for glaucoma should not be administered to anyone who is taking an MAO inhibitor or who has taken a drug from this class within the last 14 days.

The nurse is discharging a patient with a new prescription for a glaucoma medication. For which medication is it most important to remind the patient to wear sunglasses when in bright light?

Apraclonidine (Iopidine)

Apraclonidine (Iopidine) is an adrenergic agonist. This drug dilates the pupil, causing increased sensitivity to light. Patients should be taught to wear sunglasses when in the sunlight or in other bright light conditions

A patient with diabetes who is taking timolol (Timoptic) drops is admitted to the unit. What recommendations might you expect the health care provider to suggest?

Increased blood sugar checks

Timolol (Timoptic) drops is a beta blocker and can mask the symptoms of hypoglycemia if the drug is absorbed systemically. Blood glucose levels may need to be checked more often.

A nurse is caring for a young woman with glaucoma whose sight loss is severe and tells the nurse she is planning to become pregnant and breastfeed. What information should the nurse give the patient?

Breastfeeding is not recommended during glaucoma therapy.

Breastfeeding is not recommended during glaucoma therapy. Most drugs for glaucoma therapy are pregnancy category C drugs, not category X. Unless the risk for sight loss is severe, these drugs should be avoided during the first trimester of pregnancy and used with caution during the last 6 months of pregnancy.

A patient does not want to take out contact lenses before ointment administration. What rationales can be given to encourage the patient to remove his or her contact lenses? (select all that apply.)

Contacts can absorb the drug and preservative.