Pharm 12.1 Flashcards
Alzheimer’s disease
impairment of cognitive abilities that is gradual in on set but relentless in progression
alzheimer’s is the most common form of
dementing illness - gradually progressive dementia affecting cognition, behaviour, and functional status
the prevalence of alzheimer’s increases with
each decade of life
Alzheimers etilogy
?
Alzhemers cures
non
alzheimers is assiciated with deposition of
beta amyloid in the brain tissue, abnormal phosphorylation of the intracellular tau proteins causing abnormalites of microtubule assembly and collapse fo the cytoskeleton
which cells in the brain are affected with alzheimers
pyramidal cells of cortes and subcortex
one hypothesis for AD
reduced cholinergic transmission
benefit of pharmacological intervention in AD
short term benefit - do not target neurodegenerative process
treatement of AD
Anti cholinesterase inhibitors, NMDA glutamate-receptor antagonist
AChE inhibitors
tacrine, donepezil, rivastigmine, galantamine
NMDA glutamate-receptor antagonist
Memantine
AChE inhibitors are used to
selectivley inhibit AChE in CNS and elevate Ach levels in CNS
Tacrine dose limiting side effects like
HEPATOTOXICITY
Donepezil half life
long
Donepezil dose
once dailiy
Rivastigmine and Galantamine dose
2x daily
donepezil, rivastigmine, galantamine sideffects
nausea, vomiting, diarrhea
NMDA glutamate receptor antagonist are used bc
excitotoxic activation of NMDA receptors contributes to alzheimers
Memantine reduces
excitotoxicity by binding to NMDA receptors by non-competitive blcokade, slowing progression of disease
what kind of AD is memantine used
moderate to sever AD bc it reduces the rate of clinical deterioration
what is the less toxic AD treatment
memantine
memantine provides
neuroprotective effects and adverse drug effects are mild like head ache and dizziness
Glaucoma is a major cause of
blindness
glaucoma increases
intraocular tension
Without treatment of increased IOT there is
damage to the retina and optic nerve
intraocular tension is determined by
the balance btw fluid input and drainage out of the globe
aqueous humor is produced by_..and drained at__
by the ciliary epithelium, filtration angle at the anterior chanmber
treat glaucoma by
reducing production of aqueous humor, increasing the drainage of aqueous humor
90% of drainage of aqueous humor is through
the trabecular route
10% passes through
within the ciliary muscle into episcleral vessels (uveoscleral outflow)
open angle glaucoma is also callsed
chronic simple glaucoma or wide angle glaucoma
glaucoma therapy is aimed at
reducing the aqueous humor production and increasing the tone of trabecullae to facilitate drainage
glaucoma treatemnt in open angle glaucoma is mainly
pharmacolgical
closed angle glaucoma occurs when
the person has a narrow iridocorneal angle and shallow anterior chamber
in colsed angle glaucoma a dialated iris can
obstruct the outflow drainage pathway at the angle between the cornea and ciliary body (iridocorneal angle)
obstruction to the drainage of aquous humor leads to
IOT
permanent treatment for closed angle glaucoma
surgury (irodectomy), but drugs buy you some time
closed angle glaucoma can present as
acute attack (painful) as an emergency condition)
drugs for closed angle glaucoma
mannitol, pilocarpine
mannitol in glaucoma
hyperosmolar fluid to help save eye
pilocarpine in glaucoma
miotic to help save eye
beta 1 receptor present
on the base of ciliary body (beta blockers reduce aqueos humor production)
beta 2 receptor present
in the ciliary blood vessels
alpha 1 receptor present on
ciliary body blood vessels and radial muslce
alpha 2 receptor present on
ciliary body epithelium and the presynaptic sympathetic fibers supplying the ciliary body
M3 receptor present on
the circular (constrictor) smooth muscle of the iris and the ciliary muscles
treatment in open angle glaucoma
beta blockers, prostaglandins, carbonic anhydrase inhibitors, alpha agonists, cholinomimetics
beta blockers in glaucoma
timolol, betaxolol, carteolol, levobunolol, metipranolol
beta blockers for glaucoma work by
decreasing the production of aqueous humor by ciliary epitheliam (given as topical eye drops)
bc some of the drug can enter systemic absorption and cause CVS symptoms, contraindications for beta blockers are patients with
asthma, COPD, Bradycardia, heart block, heart failure
Prostaglandins for glaucoma
latanoprost, travoprost, bimatoprost
prostaglandins for glaucoma work by
increasing the aqueos drainage through the alternative pathways - uveoscleral route
carbonic anhydrase inhibitors for glaucoma
topical and systemic
topical carbonic anhydrase inhibitors
dorzolamide, brinzolamide
systemic/oral carbonic anhydrase inhibitors
acetazolamide, dichlorphenamide, methazolamide
carbonic anhydrase inhibitors for glaucoma work by
blocking the formation of aqueous humor by blocking the carbonic anhydrase enzyme required for the synthesis of it (need bicarbonate)
alpha 2 agonists fro glaucoma
apraclonidine, brimonidine
alpha 2 agonists for glaucoma work by
reducing the fromation of aqueos humor, and also exert a direct neuroprotective effect
chlinomimetics for glaumocma are either
direct acting, or indirect acting
direct acting cholinomimetics glaucoma
pilocarpine, Carbachol, Demecarium
Indirect acting cholinomimetics for glaucoma
physostigmine, echothiophate
cholinomimetics for glaucoma work by
contraction of cilliary muscle open the trabecular spaces so that aqueos humor drains more easily, iris pulled from angle fo anterior chamber bidining the filtration angle and opening the trabecular network, increased outflow of aqueos humor, decreased intraocular pressure
narrow angle glaucoma uses
mannitol/glycerol, pilocarpine/carbachol, acetazolamide, permanent treatment - laser surgery for pathway to be widened - irdotomy
other potential durges for glaucoma
PGE2, marijuana
drugs contraindicated in glaucoma (particualrly in narow angle)
antimuscuranics (ex. Atropine produces mydriasis and exacerbate problem) and alpha 1 agonists
conventional glaucoma surgery
trabulectomy
Herbal medications
Echinacea, Garlic, Ginkgo, Ginseng, Kava, Milk Thistle, St John’s wort, Saw palmetto, Dehydroepiandosterone (DHEA), Melatonin, Glucosamine
herbal medications are available
without prescription
Echinacea active constituents
chicoric acid, alkamide, polysaccharides