KMK pharmacology Flashcards
Parasympathetic
- First cell body is located at the craniosacral region of the spinal cord
- Release ACH at the pre and postganglionic neuron
- Binds to site of action
- Ciliary muscle
- Sphincter muscle
- Lacrimal gland
- M1, M2, M3 (Muscarinic receptors)
- M2 & M3 highest likelihood to be at the SOA
- Rest and digest, bronchoconstriction/miosis, SLUD (salivation, lacrimation, urination, defecation)
What enzyme breaks down ACH?
Acetylcholinesterase
What increases ACH?
Acetylcholine inhibitors
Sympathetic
- Preganglionic neuron starts at the thoracolumbar region → release a neurotransmitter
- ACH in preganglion
- epinephrine and norepinephrine (adrenaline) in postganglionic
- Fight/flight, bronchodilator, mydriasis, dry
What inhibits epinephrine?
Monoaminoxidase (MAO)
What is an example of an MAOI
Phenelzine (Antidepressant)
Causes tachycardia
What does tropicamide do?
Stops ACH to dilate the pupil
What receptor is on the dilator
alpha 1 (ex. phenylephrine)
What is the MOA of cocaine?
blocks the reuptake of norepinephrine → dilate pupils
MOA of pilocarpine
increase corneoscleral outflow
Pulls on the ciliary muscle → pulls on scleral spur → opens the TM
What are the 3 drugs that increase outflow?
Prostaglandins
Pilocarpine
Alpha 2 agonist
Cholinergic Agonist (Direct)
- Direct
- pilocarpine (rx after angle closure causing squishy iris) - makes iris tight
- After LPI
- ADies tonic pupil .125% → like water, will constrict the pupil
- pilocarpine (rx after angle closure causing squishy iris) - makes iris tight
Adies tonic pupil is a lesion in the _____.
Ciliary ganglion - starves the sphincter muscle which is why it reacts to .125% pilo
Where does thing edinger westphal start at?
midbrain (also CN 3 & 4 start here)
What are the side effects of pilocarpine?
- Has to be dosed QID - causing brow aches, myopic shift
- Create a TON of accommodation
Cholinergic Agonist (indirect)
- Myasthenia gravis
- neostigmine
- pyridostigmine (get rid of MG)
- Edrophonium (ed diganosis)
- Echothiophate (irreversible side effects)
- Donepezil (tx alzheimbers/dementia)
- Increase cholinergic or parasympathetic activity
- Increase Ach
- ALL decrease IOP
2 major ocular side effects of myasthenia gravis
- Ptosis
- Diplopia (most common SE)
- Worse at the end of the day
What can exacerbate the effects of myasthenia gravis?
B-blockers
Cholinergic Antagonist MOA
Decrease Ach
- ASH CT
- Antidepressants, Antipsychotic, Antihistamine (ANTI, ANTI, ANTI)
List longest to shortest duration of cycloplegic effects
ASH CT
- Atrophine
- Scopolamine
- Homatropine
- Cyclopentolate
- Tropicamide
Penetrates the BBB the strongest?
Scopolamine
- Amnesia
- Confusion
- Hallucination
- Can be used for motion sickness (patch)
Atropine should be avoided in which pts?
Down syndrome but overall safe drug
Shortest duration of mydriatic affects
Tropicamide - very safe drug
- Adverse reaction rare
Max effect of tropicamide
25 mins
Define penalization
Dilating the good eye with atropine
Cyclopentolate affects last how long?
24 hours - fastest onset and shortest effect for cycloplegic refraction
Max effect of cylopentolate starts at __ mins
45
Tight junction in 3 spots
- Schlemm’s canal
- Iris stroma - minor circle
- NPCE on pars plicata
Adrenergic Agonist
- Alpha 1
- Alpha 2
- Beta 1
- Beta 2
Which 2 receptors causes glaucoma?
Alpha 1 & Beta 2 (active secretion)
Alpha 1 drug
Phenyl (crappy dilation)
does not allow fixed dilation and no cyclo
Best friend during BIO (lift muellers muscle 3mm)
Alpha 2 drugs
apraclonidine & brimonidine
Nonspecific adrenergic agonist
Naphazoline
Tetrahydrozoline (visine) - ocular decongestant, takes red out, acts on alpha 1 → dilated pupil
What can you use to break PS? When is it contraindicated?
10% phenyl - increase BP, think about the heart
Avoid in TCA and graves disease, and if taking phenelzine (MAOI)
What can you use to break PS? When is it contraindicated?
10% phenyl - increase BP, think about the heart
Avoid in TCA and graves disease, and if taking phenelzine (MAOI)
3 MOA of TCA
Increase epinephrine and norepinephrine
increase anticholinergic activity
Increase serotonin
Apraclonidine
Has weak alpha 1 - no dilation
If the eye the eye does dilate with this drop then consider horner’s syndrome
Think ACUTE - acts within an hour and awesome reduction in IOP
Not good for longterm because it can cause tachyphylaxis
Brimonidine
- Alphagan 0.2%
- can cause follicular conunctivitis - red eye
- Alphagan P .10%
- has purite & a preservative
- causes miosis
If you bind to alpha 2 receptor
shut down sympathetic affects - which is why alphagan P causes miosis
Which receptors are on the lungs and eyes?
B2
Which receptors are on the heart?
B1