HEENT MOA Flashcards
Cholionomimetic agents
mimics acetylcholine & activates muscarinic receptors
Direct acting cholionometic agent
binds to ACH receptors and activates teh PNS
Indirect acting cholionomimetic agents
inhibits the breakdown of ACH by cholinesterase
this leads to an increase of ACH in the synaptic cleftr and activates the PNS
cholinometic effects on the body
- CV: slows pulse
- ENDO: increases sweat, saliva, tears
- EYE: contracts muscles of the eyes (miosis)
- GI: increased motility, secretions, relaxed intrinsic anal sphincter
- MSK: increased muscle contracts
- neurologic: improved cognition
- RESP: bronchoconstriction & increased secretion
- Urinary: contraction of bladder, relaxation of urethral spincter
Ophthalmic use of pilocarpine & carbachol (direct acting)
Binds to the muscarinic receptor and causes contraction of pupillary sphincter & ciliary muscle contraction
causes miosis
Vareicline (direct acting)
partial agonist at nicotinic receptors
for nicotine addiction
Physotigmine (indirect acting)
replinishes ACH in the synapse and prevents ACH toxicity
only cholinomimetic to travel through the BBB
Donepezil & Rivastigmine (indirect acting)
reversibly inactivate cholinesterases
Pralidoxime
prevents agining of cholinesterase enzyme (by binding)
displaces organophosphates from binding sites and regerates it
Brimonidine (alphagan P)
selective alpha 2 agonist that causes a reduction in aqueous humor formation
Timolol
beta adrenoreceptor
blocks B1 and B2 adrenergic receptors in the eye
* reduced IOP
* reduced aqueous humor production
Latanoprost (Xalatan)
opthalamic prostoglandin
prostoglandin F2-alpha analog
* reduces IOP by increasing the outflow of aqueous humor*
what drug causes increased eyelash growth
Bimatoprost (latisse/lumigan)
Bimatoprost (latisse/lumigan)
synthetic analog of prostoglandin w/ ocular hypotensive activity
* decreases IOP by increasing outflow
Pilocarpine (isopto carpine) & carbachol
directly stimulates cholinergic receptor M3 in the eye causing:
*miosis
*loss of accomadation
*lowering of IOP
Dorzolamide (trusopt) and Briznolamide
Reversible inhibition of carbonic anhydrase 2 and 4 in the ciliary epithelium
what is the result of carbonic anhydrase
Dorzolamide (trusopt) and brinzolamide
- reduction of H ion at renal tubule
- decreased aqeuous humor production
- reduced IOP
atropine
blocks ACh action that normally induces mydriasis and radial pupillary dilator muscle resulting in:
*dilation of pupil
*paralysis of ciliary muscle
antihistamines with mast-cell stablizing properties
for allergic conjunctivitis
- blocks H1 receptors at the conjunctiva & eyelids
- inhibits mast cell degranulation and limiting the release of histamine, tryptase, prostaglandin
what drugs have a MOA that inhibits mast cell degranulation
- cromlyn sodium
- nedocromil
- iodoxamide
- premiolast
naphazoline-Phinramine (Naphcon A)
Pheniramine antagonizes H1 receptors to reduce ocular pruritus and congestion
Naphazoline stimulates alpha adrenergic receptors, reducing ocular congestion and redness
Ketotifen (alaway)
opthlamic solution that selectively
olpatadine (pataday)
selectively inhibits H1 receptors and inhibits the release of histamine from mast cells