Download BHS 254.2 – Course 1 Date: 2/11/16 Hour 1 Nichole Conley Page

BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
Page 1
Answer: 2
1. Beta Blockers
a. Timolol 0.25%, 0.5% (Timoptic, Timpotic –XE)
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Introduced in 1978, still the most popular topical beta blocker
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As effective or more so than other available agents at the time (nonbeta blockers) - fewer annoying adverse reactions
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1 or 2X/day administration
- What does this really mean?
Remember: Blocking B receptors during an active sympathetic
outflow period of time is going to have more of an effect than blocking
B receptors when there is not much sympathetic activity going on.
- If the drug is taken in the morning, it is going to block those B
receptors during the day time and have more of an effect than what it
would at night time.
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Non-selective blocker (blocks both B1 and B2)
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Decreased aqueous production – beta blocker
- Remember: There is not tonic stimulation at the TM so there is no
effect to slow down outflow through the TM it is purely the B blockers
BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
Page 2
working on the ciliary body.
- The only time there is an effect on TM outflow is when we give you
a drug that activates those B receptors in the TM and increases
outflow.
*** Beta Blockers have NO EFFECT!!!!
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Duration up to 24 hours
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7X more potent than propranolol
- We can use lower concentration of Timolol compared to what we
were using with propranolol.
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Good penetration of eye
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Dark irides respond as well as light irides
- Remember: Epinephrine and pilocarpine are both bound by melanin
pigment
- Timolol and the other B Blockers are not!
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No change in pupil size or accommodation
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Decreased CNS effects vs. propranolol
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Use in all open-angle
- B blockers are effective in decreasing IOP in all of these situations
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Could be helpful in the medical management for chronic treatment of
narrow angle glaucoma
- This is not appropriate management though, these patients should be
managed by surgical correction of that narrowed angle.
- But it is used in some acute angle closure attacks
- Decreasing production, decreasing the build-up of pressure that is
occurring
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Timolol has less drop-outs in chronic treatment
- When we look at patients who have to take Timolol chronically,
which is most of our glaucoma patients, less of them quit taking the
drug or “drop out” when they use timolol versus epinephrine or
pilocarpine
- Now a days, there are even better drugs to use that are even more
BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
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tolerated by the patients such as the prostaglandins and the CA enzyme
inhibitors.
- More effective, less toxicity

Side effects – Ocular
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Irritation and lacrimation
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Dry eye
- Given systemically or topically, B blockers decrease tear production
and this can lead to dry eye symptoms.
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Allergic blepharoconjuctivitis
- Developing due to the repeated use of B blockers
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Some of the B blockers have the ability to cause local anesthetic
effects
- Remember: We use B blockers in the treatment of people with
certain types of arrhythmias. B blockers are our class II cardiac
arrhythmic drugs. They treat the arrhythmias by stabilizing the
membrane and decreasing the ability of the membrane to be excited.
- The cornea can also become stabilized or have a local anesthetic
effect in some patients.
- We can also frequently see superficial punctate keratitis with the use
of B blockers
*SPK and anesthesia are usually found together but it is not certain
how they are related or which one is causing the other or if it is just
coincidence.
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Blurred vision – with or without transient myopia
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Uveitis
- Seen most frequently as a granulomas uveitis
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Myasthenic symptoms (diplopia, ptosis, EOM paresis)
- More frequent in a patient with history of myasthenia or the use of B
blockers could help unmask a patient with this condition.
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Escape/tolerance – short-term vs.long-term drift
- Escape/ short-term drift: Some patient will return to normal IOP
BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
Page 4
within a week or two of taking Timolol and this is known as an escape
type of phenomena.
- This is why it is important to follow up with patients within a week
or two to make sure the drug is still working.
- Tolerance/ long-term drift: Some patients can also have what is
known as long term drift, where they start to slowly return back to the
IOP they had pre-treatment.
- Long-term drift can sometimes be an indication of disease
progression which is causing the IOP to once again rise.
- It may also be tolerance but not everyone demonstrates tolerance to
the B blockers.

Systemic symptoms in sensitive patients
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CNS, CV, respiration
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Others
General Information:
- When we think about Timolol as a non-selective B blocker, it’s going to block B1 and B2
receptors pretty effectively.
- With B1 we should be thinking about heart rate and when we use a B blocker to block B1
receptors we should have a decreased heart rate.
- When we think about B2 we should think about those receptors in the respiratory track and also
causing vasodilation. When we block the receptors in the lung smooth muscle were going to see
a greater risk of bronchoconstriction and in a patient with asthma or other COPD that could make
their situation much worse.
Looking down at the chart below:
Cardiovascular System: These are the B1 receptors
1. Bradycardia
2. Conduction Arrhythmias: If we are slowing the heart rate we can have problems with conduction impulses
3. Hypotension: when CO falls, BP falls
4. Raynaud’s Phenomenon: situation where you have ischemic pain in the periphery
5. Fluid retention: We have talked about B blockers being used as anti-hypertensive drugs and one of the compensatory
things happening is the retention of Na and H2O because we are lowering BP but the body wants to keep BP where it
was before drug treatment so we have fluid retention to help with that increase. That’s why a B blocker would be used
with a diuretic agent.
Pulmonary System: DO NOT GIVE TO A PATIENT WITH COPD
Bronchoconstriction/ Bronchospasm
Asthma
Dyspnea: Difficulty breathing
BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
Page 5
CNS: Much more frequent but not life threatening
Amnesia (they keep forgetting things), depression
(sometimes to the level where they need treatment),
confusion, headache, Migraine prophylaxis (people
could be taking B blockers to prevent repeated
migraine attacks), Impotence (men), insomnia and
Myasthenia.
GIT: Diarrhea and nausea
Dermatologic System:
Alopecia: (hair loss)
Nail pigmentation
Urticaria (Itching)
Lichen planus: an inflammatory reaction in the skin
Other systemic effects:
Hypoglycemia: Remember with the B blockers, it is
not that they are causing hypoglycemia, they are
blocking the symptoms of hypoglycemia in a patient
who is a liable diabetic or someone who is not well
controlled and they are up and down with their blood
sugar because the insulin
- If they are not able to respond to the symptoms of
hypoglycemia they could go into hypoglycemic shock
and could die.
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Contraindications
** In general we do not to use these in children and infants.
- Timolol (XE) has been approved to be used in children but all of the others should not be used.
BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
Page 6
b. Levobunolol (Betagan) 0.5%, 0.25% - non-selective
- This drug has a different frequency of administration because it only needs to be
given once per day compared to Timolol which needs to be given twice a day.
- This drug may have a longer duration of action but it is not certain.
c. Metipranolol (Optipranolo) 0.3% - non-selective
- This drug was the same as Timolol and Levobunolol it was just cheaper.
d. Betaxolol (Betopic-S) 0.25% suspension – selective B1 blocker
- This drug is given topically so that it can have some spill-over effects to block
the B2 receptors in the CB and be useful in the eye.
- This drug is also a benefit to patients because it is B1 selective and won’t have
as much of a problem with patients with respiratory disease.
- We will use Betaxolol in patients who cannot tolerate the other B blockers
because of their COPD.
- This drug has been successful in these patients to control their IOP and not make
their asthma worse.
- Another advantage is the 0.25% suspension that gets absorbed just as good as
the 0.5% concentration that was originally used. Decreasing the amount of the
drug given can also decrease the risks systemically and still have an equivalent
effect in the eye.
- The one disadvantage of this compound is that overall it is not as effective as
the other B blockers because it is only a spill-over effect.
BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
Page 7
This graph gives an example of the data
that proved Betaxolol worked in
patients.
- Placebo indicates no drug was given
- Dark circles are Betaxolol
- Dark triangles is Timolol
When we look at the forced expiratory
volume (FEV y-axis), there is no change
with placebo with Betaxolol and
dramatic FEV decrease with Timolol
- These patients were also given inhaled
isoproterenol which is a B agonist to
help reactivate those receptors and the
patients returned towards normal.
e. Carteolol (Ocupress) 1% solution – Intrinsic Sympathomimetic
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Activity (ISA) – non-selective
- This is a partial agonist that binds to the B receptors and stimulates
the B receptors a little bit but not enough to cause major activity.
- We would not see as great of a decrease in HR as we would with
Timolol because we are not blocking the receptor completely.
- What ISA is good for is that it doesn’t seem to disrupt the normal
lipid profile in the patient as much as the others do.
Important Note: Timolol and the other non-selective B blockers, tend to alter our lipid profile
by lowering out amount of HDL’s in the body and raising LDL’s. There has been no increased
risk of atherosclerotic disease found yet but this is just something to keep in mind.
- This doesn’t seem to happen at all with Carteolol and seems to happen much less with
Betaxolol.
BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
Page 8
This graph is simply showing
a trial of treating patients
with high IOP. They started
around 25mm Hg and we got
them down to about 19 mm
Hg and Carterolol and
Timolol had very similar
effects.
f. Combination products
a. Combigan (brimonidine 0.2% and timolol 0.5%)
b. Cosopt (dorzolamide 2.0% and Timolol 0.5%) – JR!
*Some things to consider before deciding which B blocker to use for a particular patient are
listed in the table below:
BHS 254.2 – Course 1
Nichole Conley
Date: 2/11/16 Hour 1
Page 9
Answer: 2
END FOR FINAL EXAM!!!!!!! GOOD LUCK EVERYONE !!!