Exam 1 Flashcards
1
Q
M3 Agonists role in the eye
A
o accommodation (near vision) o miosis (pinpoint) o increased drainage (conventional route) ->
2
Q
M3 Antagonists role in the eye
A
o profound mydriasis (dilated)
o may precipitate acute pressure
o increase dry eyes and loss of accommodation
3
Q
Beta Agonist Vs Antagonist role in the eye
A
beta agonist
o increase ocular fluid
beta antagonist
o decrease ocular fluid formation
4
Q
Alpha Agonists role in the eye
A
relatively weak mydriasis (a1) (dilation)
decrease fluid formation
• a2 - direct
• a1 - indirect (vascular)
5
Q
Drugs to decrease ocular fluid formation
A
o Adrenergic agonists / NET inhibitors
o Beta antagonists (Timolol)
o Carbonic Anhydrase inhibitors
6
Q
Drugs to Increase drainage of the eye through trabecular meshwork
A
o Muscarinic agonists / AChE inhibitors
o ROCK inhibitors (Netarsudil)
o Nitric Oxide
7
Q
Drugs to pull ocular fluid out & reduce fluid formation
A
- Systemic Osmolites
- Mannitol or glycerin
- Reduces ultrafiltrate in ciliary blood vessels
- Emergency cases only
8
Q
Drugs to Increase ocular drainage through uveoscleral route
A
o PGF2 analogs
o Latanoprost
o only useful in dogs
9
Q
Topical Muscarinic Blocker; use, drugs, side effects
A
used to dilate pupil
Tropicamide
• Short acting
• Good for eye exam
atropine
• long acting
adverse effects
• paralysis of ciliary muscle
• acute glaucoma
• decreased tears
10
Q
Topic alpha-adrenergic agonist use & drug
A
- used to dilate pupil
- Phenylephrine
- Not as effective as muscarinic blocker
- Useful as vasoconstrictor
11
Q
Keratoconjuctivitis sicca (dry eye); what is it? what drugs to use? side effects of drug
A
o May be immune mediated
o Dogs
Drug to use
• Topical cyclosporine
Side Effects of Drug • Suppresses immune system • Increases tears • Dry eye returns after stopping med • Rare systemic toxicities
12
Q
Drugs to use in eye inflammation
A
Topical corticosteroids
• prednisolone or dexamethasone
or NPDex
• used for conjunctiva, sclera, cornea, and anterior chamber
• deeper structures require systemic drug
• immunosuppressive and inhibit wound repair
• can worsen or cause corneal ulceration
• should not be used if viral infection present
Topical NSAID
Muscarinic antagonists
• Atropine or tropicamide
• Treat uveitis & prevent synechia and ciliary spasm pain
13
Q
Drugs to use in eye infection
A
Topical tetracyclines
• conjunctivitis in cats
• Works against chlamydia & mycoplasma
Triple antibiotic ointment
• Conjunctivitis in dogs
• Bacitracin + polymixin B + neomycin
• Systemic toxicity
14
Q
Drugs to use for viruses like feline herpes virus
A
Antivirals • Agent incorporated into viral DNA & breaks protein transcription • Nucleiside analogues = Trifluridine • Reduce signs but don’t sure virus • Need frequent dosing
15
Q
Define Pain
A
o protective mechanism to make animal withdraw from damaging situation
o can have detrimental health impacts
16
Q
Define Nociception & what are the fibers?
A
o Neural response to painful stimulus
A-delta fibers
• fast conducting
• sharp and acute pain
• easy to localize
C fibers
• slow conducting
• dull, aching, burning or throbbing pain
• hard to localize.
17
Q
Hyperalgesia & Allodynia
A
Hyperalgesia
o Exaggerated response to painful stimuli
Allodynia
o Pain due to stimuli which does not normally provoke pain
18
Q
Opioid Receptors
A
- 7 G-couple protein receptors
- Mu, delta, & kappa
- Mostly inhibitory
- Most drugs use Mu receptor
19
Q
Opioid Receptor Signaling Pathway
A
- Activation of receptor ->
- Inhibit cAMP production ->
- Open K+ channels (hyperpolarization) ->
- Close voltage gated Ca2+ channels
20
Q
Analgesic Effect of Opioids & Location Targeted
A
o Decrease chronic dull pain better than acute sharp pain
CNS
• Decrease pain perception
• Increase descending inhibitory path
Spinal Cord
• Decrease activation of spinothalamic tract by incoming nociceptor afferents
Pre-synaptic
• Inhibits glutamate release from nociceptor neurons
Post-synaptic
• Directly inhibits ascending neurons
21
Q
Sedative Effects of Opioids
A
o sedation greater in dogs than cats
o Excitement occurs in some animals: cats, horses, and huskies, sheep, cattle, swine
o Need to distinguish between agitation due to pain or drug!
o Can be used for chemical restraint
22
Q
Calming/euphoria & antitussive Effects of Opioids
A
Calming/euphoria Effects
o activate the reward centers of the brain
o how much euphoria occurs is unclear and is probably species dependent.
Antitussive Effects & Depression of Laryngeal Reflex
o Inhibition of cough center of medulla oblongata
o Dextromethorphan, Morphine, codeine, butorphanol
23
Q
GI effects of Opioids
A
o Contraindicated in pancreatitis or biliary dz
Acute:
• vomiting and defecation
• Initial stimulation of medullary chemoreceptor trigger zone (CTZ), & delayed suppression of inhibition of medullary vomiting center
later:
• cause constipation
• increase spontaneous GI smooth muscle contraction but decrease coordinated peristalsis
24
Q
Loperamide
A
o opioid that doesn’t cross the BBB at therapeutic concentrations
o used to treat diarrhea
o removed from the CNS by the efflux transporter P-glycoprotein
o can cause neurological toxicity in dogs w/ MDR1 mutation
25
Respiratory & Cardiovascular Effects of Opioids
Respiratory Effects
o decrease sensitivity of respiratory center in medulla oblongata to CO2
o Normally the cause of death in an overdose
o Less of a problem given alone
o cross the placenta and depress fetus respiratory
Cardiovascular Effects
o bradycardia more likely in animal not in pain
o can increase cardiac output in horses.
o can also cause hypotension due to vasodilation, particularly during surgery
26
Temperature Effects & Panting w/ Opioid Use
Temp Effects
o Can interfere with thermoregulation
o Most animals get hypothermic
o Cats may get hyperthermic
Panting
o may occur in some dogs, particularly after oxymorphone.
o due to resetting the thermoregulatory center in thalamus
27
Effects of Opioids on Urinary Tract & pupils
Urinary Retention
o Increase detrusor muscle and sphincter tone
o Especially common after epidural morphine
Effects on pupils
o Miosis – dogs, humans
o Mydriasis – cats, sheep, horses
28
Neuroendocrine Effects of Opioids
o Increase vasopressin (ADH) release -> oliguria
o Decrease gonadotropin release
o Increase prolactin release
29
Histamine & Opioids
o histamine release W/ IV administration of morphine.
| o cause vasodliation and hypotension
30
Acute Symptoms & Antidote for Opioid Overdose
Acute
• Miosis
• Respiratory depression
• Coma
Antidotal Therapy
• Opioid antagonists: Naloxone, Naltrexone, Diprenorphine
• Supportive respiration
31
Long Term Opioid Treatment Results
Tolerance:
• Tolerance to all effects except Miosis & Constipation
• Cross tolerance to other opioid analgesics
Dependence:
• Psychological dependence
• Physiological dependence
32
Withdrawal or Abstinence Syndrome
o opioid is stopped precipitously following chronic treatment (5-7 days)
o restlessness (thought to be craving for drug)
o vocalization, hyperactivity and aggression
o Hyperthermia,
o tremors,
o salivation
o Retching,
o Vomiting & diarrhea
33
Absorption, Distribution, & Metabolism of Opioids
Absorption
• Well absorbed
• substantial 1st pass metabolism orally
Distribution
• Lipophilic
• Well distributed
• Can accumulate in fat
Metabolism
• Many opioids metabolized via hepatic cyp/p520 enzymes and conjugated via glucoronidation
• filtered and eliminated via the kidney
• cats have low glucoronidation -> longer effects of drug
34
2 Types of Opium Alkaloids
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Morphine:
• standard narcotic analgesic
• used for severe pain
• Fairly well tolerated in most species
• can stimulate histamine release
• Can stimulate emesis
• lasts up to 4 hours
• useful for traumas and surgeries
```
Codeine:
• Antitussive
• Weak analgesic
35
Hydromorphone
* 5-7X more potent than morphine
* greater lipophilicity = faster onset time
* used for mild to severe pain
* Less histamine release
* Reduced emesis and nausea
36
Fentanyl
* 100X potency of morphine
* well tolerated in dogs and cats
* can cause excitation in horses
* no histamine release
37
Etorphine
* 1000X potency of morphine
* tranquilizer
* Mainly in zoo/wildlife vet med
38
Oxymorphone
* 10X potency of morphine
| * Less emesis, nausea, sedation and histamine release
39
Methadone
* Ocationally used in vetmed
| * treatment programs for heroin
40
Meperidine
• 1/8 potency of morphine
41
Sufentanil
• 5-10X potency of fentanyl
42
Carfentanil
* 8000X potency of morphine
| * Zoo tranquilizer
43
Buprenorphine
* Much safer than morphine
* partial agonist at mu receptors (ceiling effect)
* antagonist at k receptors
* high affinity but low efficacy
* longer duration of action than morphine
* used in mild to moderate pain
* can precipitate withdrawal if following long-term full agonist
* less highly scheduled (III) than morphine (II)
44
Butorphenol
* Antagonist at mu receptor,
* agonist at k receptor
* limited degree of analgesia
* mild to moderate pain only
* reduced side effects,
* less highly scheduled (IV),
* can precipitate withdrawal
* especially noted as better tolerated in horses (less excitement)
45
Tramadol
* Derivative of codeine
* 1/6000 the affinity of morphine for mu receptors
* Multimodal analgesia
* thought to inhibit NE and 5HT reuptake
* binds a2-adrenergic receptors
* has an active metabolite (M1) that has more potent opiate receptor binding, 200X more affinity, 6X more potent analgesia than tramadol (hepatic metabolism CYP2D6 (P450))
* better oral bioavailability than morphine
* controversial about how much pain relief it actually provides
46
Tapentadol
* mu opioid receptor agonist
* inhibits
NE reuptake
* In humans thought to produce less GI side effects
* Most concerned about respiratory depression
47
Delta Opioids
o Analgesia generally equal to morphine
o may be more effective than morphine in relief of neuropathic pain
o less addiction liability than morphine
o less respiratory depression than morphine
o less gastrointestinal side effect than morphine
48
Local Anesthetics: Mechanism of Action & Order of Sensation Loss
Mechanism of action
o Reversible block of voltage-dependent Na channels that are required for action potentials
```
Order of loss
o Small unmyelinated fibers are most sensitive
o Pain ->
o Temp ->
o Touch ->
o Joint ->
o Deep pressure
```
49
Chemical Structure of Local Anesthetics
o Weak bases
o Lipohilic group +
o Intermediate chain w/ ester or amide link +
o Hydrophilic group capable of ionization
50
Amino Esters; basics, example drugs
o local anesthetic
o Hydrolyzed by plasma esterase
o Can form PABA
o Potential allergen
Drugs
• Benzocaine
• Procaine
• Proparacaine
51
Amino Amides; basics, example drugs
```
o local anesthetic
o Biotransformedd by liver enzymes
o Rarely allergen
o Liver issues affect metabolism
o Longer T1/2 than esters
```
Drugs
• Lidocaine
• Mepivacaine
• Bupivacaine
52
Bioavailability of Local Anesthetics
o Must be uncharged to cross cell membrane & get inside cell
o BUT must be charged to block Na channel
o Inflamed tissue is acid so local anesthetics less effective
53
Routes of Administration for Local Anesthetics
Surface
• Oral spray
• Eye drops
• Patches
Conduction
• Nerve block
Spinal
• Injection into subarachnoid space
• Epidural
54
Dose Related Drug Toxicity of Local Anesthetics
CNS
• Seizures, twitching, very high CNS depression
Cardiovascular
• Dysrhythmias
• Hypotension
Methoglobinemia
• High levels of hemoglobin that doesn’t bind O2
Respiratory
• Depression if drug affects C5-C7 or CNS
55
Order of Adverse Effects of Local Anesthetics
* Analgesia
* Altered consciousness
* Muscle twitching & hypotension
* Myocardial depression & seizures
* Unconsciousness & apnea
* Cardiovascular collapse & death
56
Unusual Effects of Local Anesthetics
* Hypersensitivity or allergic reaction
| * Drug idiosyncrasy
57
Local Anesthetics Interactions w/ Vasoconstrictors
o Use w/ epinephrine, norepinephrine & phenylephrine
o Increase duration of anesthesia
o Decrease systemic toxicity
o Can cause problem w/ circulation
o Can increase risk of arrhythmias & V fib
58
Lidocaine
```
o Very versatile & widely used in vet medi
o pKa = 7.9
o rapid onset of action(1-5minutes)
o short duration(60- 120 minutes)
o metabolized by the liver
o also used IV as anti-arrhythmia
```
59
Bupivicaine
```
o Long acting (5-8 hrs)
o Slow onset (up to 20-30 mins)
o Risk of cardiac toxicity
o Metabolized by liver
o Not used IV or topical
```
60
Ropivicaine
o 5-10 min onset
o lasts 5-8 hrs
o lesk cardio & CNS risk than bupivacaine
61
Mepivicaine
o Structure similar to lidocaine
o pKa = 7.6
o onset 2-5 mins
o lasts 2-3 hrs
62
Procaine
o Non irritating
o Quick
o Lasts 45-60 mins
o Commonly used to reduce pain for IM injections
63
Proparacaine
o Used in eye
| o Fast onset & short lasting
64
NSAIDs & Analgesia
* PGs sensitize pain fibers to other chemical mediators
* NSAIDs inhibit PGs -> reduce activation of pain fibers skeletomuscular and vascular pain responds better than visceral pain
65
NSAIDs & Inflammation
* COX-2 induced at sites of inflammation
* PGs increase vascular permeability & vasodilation
* NSAIDs inhibit PGs -> decrease inflammation
66
NSAIDs & Fever
* stimulated neutrophils release ‘endogenous pyrogens’ (IL-1 and TNF-a)
* endogenous pyrogens generate PGs in hypothalamus
* PGs in hypothalamus increase temperature ‘set point’,
* fever is induced
* NSAIDs inhibit PGs -> decrease fever
67
NSAIDs & Platelets
* NSAID targets COX-1 -> inhibits platelet aggregation
* NSAID targets COX2 -> platelets aggregate
* TXA generated by platelets causes aggregation
* PGI generated by endothelial cells inhibits aggregation
* aspirin has an irreversible action
68
NSAIDs & Gastric Ulcers
* Most common side effect of these drugs
* PGI and PGE inhibit acid secretion and stimulate cytoprotective mucous secretion
* can cause secondary anemia due to gastric bleeding
* not as much an issue with COX-2 selective agents
69
NSAIDs & Renal Blood Flow
* COX-1 maintains GFR
* COX-2 regulates Na+ reabsorption
* inhibition causes salt and water retention
(reduced renal blood flow)
* prolonged use can lead to papillary necrosis and nephritis
70
NSAIDs & the Heart
* concern for all COX2 selective agents
| * COX2 inhibition encourages thrombic events
71
Salicylates (Aspirin); basics, signs of acute overdose
o used in all species, but high tendency towards gastric ulceration
o can induce hepatic damage,
o detrimental to cartilage
o has been replaced by newer and safer NSAIDs
o irreversible inhibition of cyclooxygenase = anti-platelet compound
o metabolized via glucuronidation (slow in cats!)
acute overdose
• respiratory actions via CNS
• acid/base problems
72
Pyrazolone Derivatives (Phenylbutazone)
o very popular in equine
o used for bone, joint, & soft tissue pain
o problems associated with blood disorders
o certain pony breeds very sensitive to GI effects
o classic microsomal enzyme inducer (many drug interactions!)
o T1/2 cattle = 40 hr
o T1/2 horse = 6hr
o drug has tendency to accumulate
73
Proprionic Acid Derivatives
o Reversible inhibition of cyclooxygenases
```
Carprofen
• approved in dogs for osteoarthritis
• high selectivity for canine COX2
• high safety level in dogs
• thought to inhibit PLA2
• liver metabolism
• rare hepatotoxicity ( reversible if caught early)
```
Naproxen
• Use in horses
• Many adverse reactions in dogs
Ibuprofen
• Serious GI erosion in dogs
74
Nicotinc Acid Derivatives (Flunixin meglumine)
o Horses IV or IM to treat visceral pain (colic)
o Cows IV for pyrexia, endotoxemia, inflammation
o Dogs in septic shock
o Causes GI upset in dogs
o Use for only short duration
75
Oxicams (Meloxicam)
* COX2 selective
* in dogs osteoarthritis & post op pain
* in cats post-operative pain – one dose only (fatal kidney damage)
76
Coxibs (Robenacoxib)
o Highly COX2 selective
| o One of few NSAIDs for cats
77
Piprants (Grapiprant)
o PG receptor antagonist
o recently approved for use in dogs (2016)
o Targets EP4 receptor
o Helps with pain and inflammation associated with osteoarthritis
o preserves PGE2 action at other EP receptors (e.g., GI tract)
o so far relatively mild toxicities have been seen
78
Aceteminophen (Tylenol)
```
o analgesic and antipyretic
o only weakly anti- inflammatory
o COX3 inhibitor
o not effective on platelets
o low incidence of GI side-effects
o hepatic damage
o not used in veterinary medicine
o generation of toxic metabolite prevented by glucuronidation
o TOXIC to CATS
```
79
elete
Delete
80
Control of Release of cortisol & ACTH
* ACTH released by stress & diurnal rhythm ->
* ACTH acts on fasiculata/reticularis to release cortisol ->
* cortisol feeds back to reduce ACTH release
81
Receptors for Glucocorticoids
* found on almost every cell in body
* Mostly glucocorticoid (GC) receptors
* Some mineralocorticoid (MC) receptors
82
Metabolic Effects of Glucocorticoids
o Decrease insulin sensitivity
o Release protein from muscle & lymph for glucose production
o Release fat from adipocytes & redistribute to central compartment
o Increase gluconeogenesis & glycogen storage in liver
83
Actions of Glucocorticoids on CNS
o sense of well being
o decrease sensory acuity
o other behavioral effects
84
Actions of Glucocorticoids on Cardiovascular
o decreases vascular permeability
o Maintain catecholamine effects on vasoconstriction
o Maintain cardiac contractility
o Excess can lead to hypertension
85
Actions of Glucocorticoids on Kidneys
o needed to concentrate or dilute urine
o excess interferes with ADH action
o excessive drinking/urination = early sign of overdose
86
Actions of Glucocorticoids on GI
o Increases gastric acid secretion (via decrease PGs)
| o inhibits Ca2+ and PO4 absorption
87
Actions of Glucocorticoids on Bone
o decrease turnover
| o increases reabsorption
via indirect decreased absorption of Ca2+ from GI tract
88
Actions of Glucocorticoids on Connective Tissue
o excess causes decrease in collagen synthesis
89
Actions of Glucocorticoids on Hematopoietic System
o pharmacological doses decrease proliferation of B and T lymphocytes
o high doses kill lymphocytes
o reduced size of thymus, spleen, and lymph nodes
o increased neutrophils, platelets, & rbc’s
o decreased eosinophils
90
Anti-Inflammatory Actions of Glucocorticoids
o Decrease proliferation, differentiation, and survival of inflammatory cells (T lymphocytes and macrophages)
o Prevent release of histamine, serotonin, and lyzosomal enzymes
o Decrease generation of arachidonic acid metabolites (prostaglandins and leukotrienes)
o Prevent release and actions of IL-1, IL-2, TNF-a
o Inhibit release of cell adhesion molecules reducing recruitment of inflammatory cells
91
Uses for Glucocorticoids in Musculoskeletal, skin, renal, GI, Lungs
Musculoskeletal
• arthritis, bursitis, tendenitis, myositis
Skin
• allergic dermatitis, otitis externa
Renal
• glomerulonephritis
GI tract
• colitis, gastroenteritis
Lungs
• asthma
92
Adverse Reactions of Glucocorticoids
```
o PU/PD
o Polyphagia
o Muscle weakness
o Osteoporosis
o Fat mobilization
o Pancreatitis
o GI ulcers
o Seizures
o Diabetes
o K+ loss & Na+ retention
o Prone to infection
o Slow wound healing
o Corneal ulcers
o Hypogonadism
o Lethargy, depression, behavioral change
o Hepatomegaly
o Blunted HPA axis
o GI issues
o Laminitis
o Drug interactions
```
93
Strategies to Reduce Side Effects of Glucocorticoids
o Use minimal dose for shortest time
o Intermittent dosing
o Supplementing protein, Vit D & A, & K+
94
T1/2 in Plasma & Time till Tissue Effect of Cortisol, Cortisone, Prednisone, Prednisolone, Fludrocortisone, & Dexmethasone
JUST REMEMBER WHICH DRUGS ACT LONGER THAN OTHER
Cortisol
• T1/2 Plasma = 90 min
• Tissue = 8-12 hr
Cortisone
• T1/2 Plasma = 30 min
• Tissue = 8-12hr
Prednisone
• T1/2 Plasma = 60 min
• Tissue = 12-36hr
Prednisolone
• T1/2 Plasma = 200 min
• Tissue = 12-36 hr
Fludrocortisone
• T1/2 Plasma = 200 min
• Tissue = 8-12hr
Dexmethasone
• T1/2 Plasma = 200 min
• Tissue = 36-54 (too long for alternate day therapy)
95
Relative GC & MC (kidney) Potency of Cortisol, Cortisone, Prednisone, Prednisolone, Fludrocortisone, & Dexmethasone
#s AREN'T IMPORTANT JUST REMEMBER WHICH DRUGS HAVE MORE GC OR MC
Cortisol
• GC & MC = 1
Cortisone
• GC & MC = 0.8
Prednisone & Prednisolone
• GC = 4
• MC = 0.8
Fludrocortisone
• GC = 10
• MC = 125
Dexmethasone
• GC = 25
• MC = 0
96
Cortisol & Cortisone
* Cortisol is natural GC.
| * Cortisone needs to be converted to cortisol
97
Prednisone & Prednisolone
* Widely used GC
* Prednisone is converted to prednisolone (active) in the liver
* If liver disease may not convert
* Cats have a limited ability to convert, therefore prefer prednisolone (& horses)
* Clinician preference
98
Dexmethasone
* Extremely strong GC
* very powerful to treat signs initially
* Longer term use = more side effects
* not useful for alternate day dosing
99
Fludrocortisone
* Used to treat hypoadrenocorticism in dogs and cats
* Has both MC and GC
* While GC is lower it is sufficient to restore GC activity
100
Nutraceuticals
o Symptomatic Slow-Acting Drug for Osteoarthritis
o oral
o effectiveness questionable
o sold as supplements
101
Hyaluronate
o Symptomatic Slow-Acting Drug for Osteoarthritis
o Restores synovial fluid viscocity
o Given intra-articular
o Works best when degeneration isn’t severe
102
Polysulfated Glycosaminoglycans
o Symptomatic Slow-Acting Drug for Osteoarthritis
o Isolated from bovine cartilage
o Use in horses & dogs
o inhibits proteolytic enzymes that degrade proteoglycans
o precursor for proteoglycan synthesis
o decreases PGE2 levels
o increases hyaluronic acid concentration in synovial fluid
o actions are slow
o prolonged use can help maintain joint cartilage
o intra-articular or IM
o interfere w/ platelet aggregation
103
Glucocorticoids for Osteoarthritis
o intra-articular injection
o long acting (3-4 weeks)
positive effects
• decreases release of lyzosomal enzymes
• inhibits PG synthesis
• relieves pain and inflammation
negative effects
• catabolic - will inhibit repair process
• decrease hyaluronate synthesis
• may obscure true degenerative process
104
NSAIDs used for Osteoarthritis
Carprofen
o Kidney & liver issues prevalent in older animals
Gapiprant
o EP4 receptor antagonist
o PGE2 interacts with EP1, EP2, EP3, and EP4
o EP4 receptors mediates PGE2 effects to cause pain and swelling
o preserves PGE2 functions at other sites
o newer agent with limited experience
105
Dimethylsulfoxide
o Free radical scavenger
o vasodilator
o analgesic action (inhibits PGs generation)
o Topical
o Rapidly absorbed
o Labeled for reduction of acute swelling and trauma
106
Timolol
o beta antagonist
o lower occular pressure
o decrease occular fluid
o use carefully w/ respiratory or heart dz
107
Demecarium
o Acetylcholinesterase inhibitor.
| o Improves fluid drainage
108
Pilocarpine
o muscarinic agonist
o lowers intra ocular pressure
o improve fluid drainage
109
Epinephrine
o mixed α−β-adrenergic receptor agonist
| o decrease occular pressure & fluid formation
110
Dorzolamide
o carbonic anhydrase inhibitor
| o reduces occular fluid formation
