Pharm Flashcards
What was the 1st glaucoma drug invented?
Pilocarpine
NOTE: short half life so need frequent admin (QID). Reduces pressures by 30%
MOA of Pilocarpine?
(+) longitudinal muscles of CB (corneo-scleral pathway) –> pulls posteriorly on scleral spur & secondarily opens up trabecular spaces for INC outflow & DEC IOP
Pilocarpine is considered what kind of drug?
Direct cholinergic agonist
Uses for pilocarpine?
- After an angle closure attack in prep for LPI
- 1% –> DDx 3rd nerve palsy from sphincter tear in pt w fixed, dilated pupil - 3rd nerve palsy WILL constrict
- 0.125% DDx Adie’s Tonic Pupil (acute dilated pupil); iris sphincter is super sensitized
ADEs of pilocarpine?
- Browaches, HA, myopic shift (pt will INC their accom bc it is paralyzed causing shift)
- Miosis
- Cataracts
- Retinal Detachments
- Secondary angle closure
Neostigmine, edrophonium, echothiophate, and pyridostigmine are considered what kind of medications?
Indirect Cholinergic Agnoists: Anti-cholinesterase agents
NOTE: this is considered “indirect” bc it inhibits AchE which is the enzyme that breaks down ACh
Which is the most dangerous cholinergic antagonist?
Scopolamine
NOTE: similar clinical indications as atropine but rarely used side effects
ADEs of scopolamine?
Hallucinations, amnesia, unconsciousness, confusion, restlessness, incoherence, vomiting, urinary incontinence
Major actions of parasympathetic nervous system?
- Broncho-constriction
- Miosis
- Rest and digest
- INC in secretions (SLUD): salivation, lacrimation, urination, defecation
Major actions of sympathetic nervous system?
- Broncho-DILATION
- Mydriasis
- Fight or flight
- Overall DEC in secretions (anti-SLUDGE)
What receptors are on the iris sphincter?
M3
Effect = miosis
RECALL: the iris muscles develop from NEURAL ECTODERM
What receptors are located on the ciliary muscle?
M2, M3
Effect = accommodation
RECALL: ciliary muscles develop from the neural crest. Abnormal neural crest development –> irregular iridocorneal adhesions
What receptors are located on the lacrimal gland?
M2, M3
Effect = tear production
RECALL: lacrimal gland is derived from surface ectoderm. Surface ectoderm gives rise to “surface” structures.
What receptor is located on the iris dilator?
a. Alpha 1
b. Alpha 2
c. Beta 1
d. Beta 2
e. M2
f. M2 & M3
a. Alpha 1
RECALL: Alpha 2 --> CB vasculature Beta 1 /2 --> NPCE Beta 2 + M2/M3 --> Ciliary muscles, TM M3 --> Iris sphincter M2/M3 --> Lacrimal gland
What receptors are located on the Ciliary Muscles & Trabecular meshwork?
Ciliary Muscles: M2/M3 + Beta 2
Trabecular Meshwork: Beta 2
Beta 2 agonists cause what to the TM & CM & NPCE?
RELAXATION
INC outflow & DEC Accommodation & INC IOP
Which cholinergic antagonist works the fastest and has the shortest duration of MYDRIATIC effect?
Tropicamide
What are the ADEs of Atropine?
1 is DRY MOUTH
Dry skin
Rapid pulse
Disorientation
Fever due to CNS effects of hypothalamus
NOTE: do NOT give to pts w DOWN’s SYNDROME, small children, and elderly
Which anti-cholinergic antagonist has the fastest onset & shortest duration of CYCLOPLEGIC effects?
Cycloplentolate
NOTE: this drug is the standard for cycloplegia in clinic
Which anti-cholinergic antagonist is the standard for Treating ANTERIOR Uveitis?
Homatropine
- Keeps iris MOBILE (DEC likelihood of posterior synechiae formation)
- REDUCES pain by paralyzing CM & sphincter
- Stabilizes the BAB by constricting the iris & ciliary body vasculature to limit passage of blood contents into the aqueous humor
Which medication is a SOMATIC drug that blocks the release of ACh at the neuromuscular junction, inhibiting muscle contractions?
Botulin A Toxin (Botox)
Single injections have been effective in providing permanent correction for strabismus; cosmetic wrinkles
Used in blepharospasm Tx but effects only laast a couple hours
What are the uses of adrenergic agonists?
- Promote SYMPATHETIC activity
- Used in dilation, conj constriction, & management of minor allergic conditions
- Temporary control of IOP spikes (post Sx, angle closure glaucoma, Tx POAG)
What receptors does Norepinephrine act on?
A1 (dilator)
A2 (CB vasculature)
B1 (NPCE + heart)
NOT B2
What receptors does Epinephrine act on?
A1 (dilator)
A2 (CB vasculature)
B1 (NPCE + heart)
B2 (Lungs)
MOA of Phenylephrine (neo-synephrine)?
Alpha-1 Agonist!!!!
ONLY dilates. Not effect on Beta receptors so NO cycloplegic effect
Alpha-1 receptors are MAINLY on SMOOTH MUSCLE & blood vessels (will cause constriction and INC BP)
NOTE: muller’s muscle contains alpha-2 receptors and some alpha 1 receptors so it will retract potentially w phenyl use
Other uses for Phenylephrine other than to help dilation?
- DDx scleritis vs episcleritis (blanch = epi)
- Horner’s syndrome
- 10% to break PS but has adverse CV effects (HTN)
CI of phenylephrine?
MAOIs
TCAs
Grave’s Dz
What medications is this description describing?
- Topical ocular decongestants
- Alpha»_space; Beta effects (potential to depress the CNS)
- Fixed dilated pupil potentially
- Naphazoline (Naphcon)
- Tetrahydrozoline (Visine)
Visine may cause fixed dilated pupil
Naphcon-A is a popular OTC combines the reduction of hyperemia & anti-histamine for itch relief
What are the two main alpha-2 topical adrenergic agonist used for glaucoma?
- Brimonidine (Alphagan 0.20%)
2. Apraclonidine (Iopidine)
Which ocular glaucoma medication fits this profile:
- Highly selective alpha-2 agonist (30X more selective than the other in its class)
- Neuroprotective properties
- 30% Follicular conjunctivitis
- TID due to short duration
- Miosis ADE (helps w post-refractive LASIK, PRK complaints)
- Systemic dry mouth (MC) and CI of MAOIs
Brimonidine (Alphagan 0.20%)
Which ocular glaucoma medication fits this profile:
- BEST eye drop to drop IOP in acute situations
- Used: control IOP spike before & after Sx, laser iridotomy, trabeculoplasty, posterior capsulotomy
- Also used for Acute Angle Closure; rapid potent DEC IOP
- 30 to 40% IOP reduction
- Onset: 1 hour, peak 3-5
- Tx: tachyphylaxis
- Dx Horner’s
Apraclonidine (Iopidine)
What are the pharmacological tests for Horner’s Syndrome?
- Cocaine
- Apraclonidine
- Hydroxyamphetamine
- Phenylephrine 1% (Adrenergic receptors are sensitized)