Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Z Glaucoma > Final - Beta Blockers > Flashcards

Final - Beta Blockers Flashcards

1
Q

Beta 1

A

Found in heart

Stimulation causes incr HR, cardiac contractility, AV conduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Beta 2

A

Found in bronchial muscle, BVs, uterus

Stimulation causes dilation of bronchi, BVs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Beta 3

A

Recently IDd in mammals

Mediation of lipolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Beta-adrenoreceptors antagonists

  • ocular
  • inhibition
  • classification
A

Topical ocular BBs (OBBs) are beta-adrenoreceptor antagonists

Competitive inhibitors

Selective (either 1 or 2)*
Non-selective (1 and 2)
*at high levels, act on all beta receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

OBB MOA

A

Reduce aqueous formation
No change in outflow
Decr up to 50%

Exact mechanism unclear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

OBB MOA classic hypothesis

A

Inhibits receptor -> stops activation of G protein -> stops stimulation of adenyl cyclase -> stops catalyzation of ATP to cAMP -> stops production of aqueous from ciliary process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

OBB MOA alternate hypothesis

A

Ciliary process are under continuous tonic stimulation to produce aqueous (mediated by epi)

BBs interfere with tonic stimulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

OBB indications

A

OHT and open angle glauc
Secondary or angle closure glauc

May be standalone or with other drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

OBB contraindications

A

Relative/absolute: pulmonary disease, bronchial asthma, severe COPD
-betaxolol (selective, is not contraindicated for above)0

Any pt with: sinus brady (<60bpm resting), overt CHF, hypersensitivity to drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

OBB treatment regimen

A

QD or BID

  • BID may lower greater than QD
  • more practitioners use QD and incr to BID if needed (minimize SE)

Don’t use BID:

  • isatalol (QAM)
  • tomoptic XE or GFs (QD)
  • betagan (QD)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Timolol

  • available as
  • vs other BBs
  • pts
A

Timolol maleate or hemihdrate, 0.25% or 0.5%
-maleate 0.5% commonly used

Non-selective
No corneal anesthesia (like propranolol)
Greater efficacy than pilocarpine

Lowers IOP in normals, OHT, and glaucoma pts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Timolol

  • good alternative to
  • onset
  • peak action
  • max effect
  • IOP lowering persists for
A

Prostaglandins

30min

2 hours

Can persist for 12 hours

Persists for 24 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Timolol

-AM vs PM

A

AM reduces IOP below baseline

PM does not reduce below baseline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Timolol

-short-term escape

A

Not in all pts

Efficacy decr over time (several weeks)

Response of beta receptors to contstant antagonism

May be an up-regulation of receptors in target tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Timolol

-long-term drift

A

Over months-years

Control of IOP not as good as once

Washing out and re-starting helps restore levels

  • clinically = 4 week wash-out period
  • IOP effects may last 2 weeks
  • aqueous flow up to 6 weeks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Gels vs gtts

A

Gels

  • improve bioavailability
  • decr systemic absorption
  • QD instead of BID = better adherence/compliance (?)
  • blurs vision
  • Timoptic XE preserved with benzododecinium bromide (not BAK)
17
Q

Istalol

  • what it is
  • claims
  • efficacy
A

Timolol maleate 0.5%

  • formulated with potassium sorbate
  • lower BAK concentration

Enhances bioavailability (QD)

Most visits IOP difference is within 1.0mmHg b/w groups
-all visits within 1.5mmHg (compared to BID)

18
Q

Betaxolol hydrochloride

  • type
  • concentration
  • solution
A

Selective BB

0.25% suspension of resin coated beads (gradual release)

Not available in USA

19
Q

Betaxolol suspension

A

Less ocular irritation vs solution

Less effective vs Timolol

Advantage is selective BB - can be used in pts with pulmonary disease

20
Q

Local SE

  • propanolol
  • other OBBs
  • discomfort, burning, stinging
  • BAK’s purpose
A

Corneal anesthesia

No anesthesia

Due to active molecule, pH, preservative, vehicle

Helps with penetration

  • sensitivity not uncommon
  • preservative free is available, very expensive
21
Q

Local SE:

  • BAK issues
  • metipranolol
A

Multiplies/exacerbates BB issues

  • decr tear production
  • decr goblet cell density
  • dry eye symptoms
  • ocular cicatricial pemphigoid

Assoc with granulomatous uveitis

22
Q

Systemic SE

  • how enter system
  • oral dose
A

Via nasolacrimal system (almost like IV dose of meds)

20-60mg, OBBs do not approach oral dose

23
Q

CNS adverse effects

A

Anxiety, depression, fatigue, lethargy, confusion, sleep disturbance, memory loss, dizziness

Sexual dysfunction

  • decr libido
  • impotence in men

Less CNS effects with betaxolol

24
Q

Cardiovascular SE

  • BBs in general
  • OBBs
A

Blocking beta 1 = lower HR, lower BP, decr myocardial contractility, slowed conduction time

Decr HR, significant bradycardia, lower BP

  • always check BP and pulse rate on pts rxd or on OBBs
  • timoptic XE/other gels less effect (gels stay in the eye, less systemic absorption)
25
Q

Pulmonary SE

A

Due to blockade of beta 2

Betaxolol has been used safely in pts with pulmonary disease

26
Q

Drug-disease interaction: diabetes

  • symptoms
  • who is most at risk
A

Hypoglycemia = nervousness, sweating, intense hunger, trembling, weakness, palpitations

True problem in insulin-dependent pts

Z Glaucoma (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions