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Flashcards in Eye Pharm Deck (32)
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1
Q

Which is a PDE inhibitor that affects vision?

A

Viagra

2
Q

Name the 2 opposing muscles (IRIS) that control the opening of the pupil AND their receptors.

A

1) Pupillary Dilator - ALPHA adrenergic receptor

2) Pupillary Constrictor - muscarinic (M) receptor

3
Q

Name the autonomic receptor on ciliary muscle that controls accommodation and facilitates aqueous humor outflow

A

Muscarinic (M) receptor

4
Q

Name the autonomic receptor on ciliary epithelium (ciliary body- produces aqueous humor)

A

BETA adrenergic receptor

5
Q

What two categories of drugs can be used to induce MYDRIASIS to facilitate an ophthalmic exam?

A

PHENYLEPHRINE (alpha agonist) - to act on pupillary dilator

TROPICAMIDE (anti-muscarinics) - to antagonize pupillary constrictor

6
Q

What class of drugs is used to generate CYCLOPLEGIA (accommodation blockade)

A

Anti-muscarinics

7
Q

What are the two classes of drugs that can be used to reduce intraocular pressure (IOP)?

A

MUSCARINIC Agonists - To facilitate AH outflow

CHOLINESTERASE Inhibitors - Same effect

8
Q

Name the three anti-muscarinics

1- prototype, 1- derivative

A

1) ATROPINE - Prototype
2) SCOPOLAMINE - Derivative
3) TROPICAMIDE

9
Q

Which of the anti-muscarinics can be used as a transdermal patch for motion sickness?

A

SCOPOLAMINE

10
Q

Describe the pharmacokinetics (Absorption of ADME) of anti-muscarinics.

A

Both atropine and scopolamine are absorbed from the GUT and CONJUNCTIVA -> Antagonize the ciliary muscle + pupillary constrictor

11
Q

Pneumonic for symptoms of ANTIMUSCARINIC EXCESS

A

Dry as a bone, Blind as a bat, Mad as a hatter, Hot as hell, Red as a beet, Full as a flask

12
Q

ANTI-MUSCARINIC EXCESS 1:

Dry as a Bone

A

Decreased sweat, lacrimal gland secretion (tears), and salivary gland secretion (salivation)

13
Q

ANTI-MUSCARINIC EXCESS 2:

Blind as a Bat

A

Cyclopegia (Ciliary Muscle Paralysis) - Eyes are fixed to far objects -> Can NOT accommodate lens to focus on near objects

14
Q

ANTI-MUSCARINIC EXCESS 3:

Mad as a hatter

A

Decrease in Ach = CNS Excitation

Restlessness, Irritability, Disorientation, Delirium, Hallucination

15
Q

ANTI-MUSCARINIC EXCESS 3:

Hot as hell

A

Decreased ability to sweat

16
Q

ANTI-MUSCARINIC EXCESS 4:

Red as a Beet

A

Decreased ability to sweat -> Cutaneous vasodilation to try to facilitate heat dispersal

17
Q

ANTI-MUSCARINIC EXCESS 5:

Full as a flask

A

Inability to contract bladder -> Urinary retention

18
Q

How does anti-muscarinic excess affect adults and children?

A

ADULTS: Not life-threatening
CHILDREN: Life-threatening due to hyperthermia

19
Q

TREATMENT (3) : Anti-muscarinic Excess

A

1) Cooling blankets
2) Benzodiazapines (DIAZEPAM) - Seizure Control
3) Cholinesterase Inhibitor (PHYSOSTIGIMINE)

20
Q

Why is TROPICAMIDE used as a mydriatic, cyclopegic agent in ophthalmic exams rather than ATROPINE or SCOPOLAMINE?

A

Tropicamide’s Duration of Effect is SHORTER (4 hrs) as opposed to atropine and scopolamine (7-10days, 3-7days). Do not have to worry about anti-muscarinic excess

21
Q

What eye pathology is ATROPINE particularly useful for? Why?

A

AMBLYOPIA (Lazy Eye) - Longer Half-life

Induces cyclopegia in STRONGER eye so that brain is forced to use and strengthen the weaker eye

22
Q

What is the ALTERNATIVE, Second line of treatment for amblyopia?

A

Scopolamine (Patch)

23
Q

Name the two components of SECRETING and FACILITATING aqueous humor outflow.

A

1) Ciliary Body Epithelium (beta adrenergic receptors) - Secrete AH
2) Ciliary Muscle (M receptors) - Contraction puts tension on TRABECULAR MESHWORK -> Facilitates outflow through the canal of Schlemm

24
Q

Name the two classes of drugs used to treat glaucoma.

A

1) BETA ADRENERGIC BLOCKERS - ANTAGONIZE AH production by ciliary epithelium
2) CHOLINESTERASE INHIBITORS - AGONIZE ciliary muscle contraction that puts tension on the trabecular meshwork -> Increase AH outflow -> Decrease IOP

25
Q

What is the FIRST line of treatment for gluacoma?

A

LATANOPROST

26
Q

What is the mechanism of action of LATANOPROST?

A

Prodrug for PGF2alpha

Acts on prostaglandin receptors -> Increases UVEOSCLERAL outflow of AH

27
Q

What are three classes of drugs that DECREASE Aqueous humor production to combat glaucoma?

A

1) BETA BLOCKERS - Timolol
2) CARBONIC ANHYDRASE INHIBITORS - Brinzolamide
3) ALPHA-2 AGONISTS - Apraclonidine

28
Q

What are the two classes of drugs that increase uveoscleral outflow to combat glaucoma?

A

1) LATANOPROST (PGF2alpha prodrug)

2) APROCLONIDINE (alpha-2 agonist)

29
Q

Which two classes of drugs contract ciliary muscle fibers, thereby increasing aqueous humor outflow to combat glaucoma?

A

1) CHOLINERGIC AGONIST - Pilocarpine/Carbachol

2) CHOLINESTERASE INHIBITOR - Echothiophate, Physostigimine

30
Q

Clarification on UVEOSCLERAL OUTFLOW

A

90% of aqueous humor drains through angle of the eye -> canal of schlemm -> Venous system
10% follows an unconventional pathway (UVEOSCLERAL OUTFLOW) - Fluid flows through the ciliary muscle -> Suprachoroidal space

31
Q

Which class of drug is used for CLOSED ANGLE GLAUCOMA? Name the two (1 oral, 1 IV) drugs within this class.

A

OSMOTIC AGENT - Increases osmotic gradient between eye and circulating blood -> Increases fluid efflux
ORAL glycerol
IV mannitol
Acts within 10mins

32
Q

How do topical eye drugs access the systemic circulation?

A

NASAL ABSORPTION - Lacrimal drainage -> Nose (highly vascular mucosal epithelium) -> Circulation