Intro drugs and cholinomimetics Flashcards
Antihistamines- what is the difference between first and second generation?
First generation were hydrophobic- crossed the BBB and make you drowsy. Used as sedatives.
Second generation are polar so cannot cross the BBB = no drowsiness.
L-DOPA- what is it used to treat? Why is it used? What is it co-administered with and why?
Used to treat Parkinsons. Dopamine is too polar to cross the BBB so L-DOPA (lipohilic) is administered, diffuses through BBB and converted to Dopamine by DOPA decarboxylase. Co-administered with Carbidopa, which inhibits DOPA decarboxylase outside the BBB, but is also to polar to cross the BBB.
Pilocarpine- what class is it? What type of drug is it? A property? Half-life? Treats? Side effects?
Alkaloid. A non-selective muscarinic agonist, a directly-acting cholinomimetic. Good lipid solubility. Half life 3-4 hrs. Treats glaucoma. Side effects: blurred vision, sweating GI disturbance and pain, hypotension, resp distress.
Bethanechol- what class is it? What type of drug is it? Two properties? Half-life? Treats? Side effects?
Choline ester. An M3 AchR selective agonist, a directly-acting cholinomimetic. Resistant to degradation and orally active. Half-life 3-4 hours. Assists bladder emptying and gastric motility. Side effects: sweating, impaired vision, nausea, bradycardia, hypotension and resp difficulty.
Physostigmiine- what type of drug is it? How does it work? Where does it work? Half life? Treats? (2)
Indirectly-acting cholinomimetic drug- a reversible cholinesterase inhibitor Increase the duration of endogenous Ach activity in the synapse by donating a carbamyl to the enzyme, which blocks the active site and takes minutes to be hydrolysed. Works mainly at postganglionic parasympathetic synapses. Half life- 30 minutes.Treats glaucoma and atropine poisoning.
Ecothiopate- what class of drug is it? What type of drug is it? How does it work? Treats? Systemic side effects?
An oranophosphate compound. Indirectly-acting cholinomimetic drug- an irreversible cholinesterase inhibitor. Works by donating a large blocking group to the enzyme’s active site that is stable and resiatnt to hydrolysis. Reovery via new enzymes takes days/weeks. Treats glaucoma. Side effects include sweating, blurred bision, GI pain, bradycardia, hypotension, resp diffcilty (sim to bethanechol).
