PHAR301 Flashcards
(147 cards)
phenytoin
-works on partial and generalized tonic-clonic seizures.
-Act by blocking Na channels
-Its metabolism has saturation kinetics (can only get rid for a fized a mount of phenytoin in a given time, therefore it is very hard to find the right dose. The DR is very steep)
Also phenytoin is n competition with aspirin (can have overdose of phenytoin)
-It can induce gingival hyperplasia and hirsutism
carbamazepine
- works on partial and generalized tonic-clonic seizures. Works by blocking Na+ channels
- can have drug-drug interactions with contraceptive pills
valproate (vigabatrin)
- works all partial, absence and generalized tonic-clonic seizures.
- Acts by blocking Na+ channels and increases GABA transmission by inhibiting GABA-T
ethosuxamide
- Works only on generalized absence seizures
- Blocks (inhibits) T-type Ca channels found on thalamocortical neurons which is part of the pacemaker activity of these cells in therapeutic doses
phenobarbital
-Works on partial and generalized tonic-clonic seizures
-Increases GABAa (stimulate the receptor function) and decreases (NMDAreceptors) glutamine transmission
-Side-effects: hepatic microsomal enzymes, possibility of overdosesedative, teratogen.
(NMDA receptor blockers produce ataxia)
benzodiazepine (e.g diazepam)
- Drugs of choice for status epilepticus. The drug is given as a an emergency.
- they work on all partial, generalized tonic-clonic and absence seizures
- Increase GABA transmission (contrarily to phenorbarbital on its own who can open GABA channels, BZ needs an agonist to work.
Sinemet
- L-Dopa + Carbidopa
- gives the most complications (dyskinesia), but the most effective drug. It becomes less and less useful
selegiline (deprenyl)
- Treament for parkinsons
- Inhibits MAO B (which converts MPTP into MPP+)
- Could be neuroprotective by blocking the conversion of MPTP into neurotoxic MPP+ and inhibiting conversion ofDA into free radicals.
- Can last 1 year before using L-Dopa
DAT blocker e.g Nomifensine
-prevents MPP+ from entering the DA neurons
DA agonist e.g bromocriptine
-Drug for parkinsons
-should work in complete absence of DA
-Fewer oxyradicals because of less DA release
-Longer half-life thn L-DOPA
work better in animals than in humans. It is less effective than L-DOPA. useful in early PD (can last 5 years before using L-DOPA). Useful adjunct use with L-Dopa
terfenadine
-has long-lasting blocking effect
with increasing dose, its effect goes down because of the fact that it is a competitive antagonist, slow dissociation (when it binds to the receptor, it basically stays there) and that it occupies almost all spare receptors
hydrochlothiazide
- Antihypertensive drug
- Diuretic (thiazide family)
- Preferred first drug.
- for mild to moderate HT.
- Work on distal convoluted tubules. (Block Na+/Cl- symporter, augment Ca++ absorption)
- Orally active.
- Toxic when there is K+ depletion (hypokalemia) which is not good for patients who experience arrhythmia.
Furosemide
- Antihypertensive drug and congestive heart failure (increase CO)
- Loop diuretic family
- They work very quickly.
- For moderate to severe HT.
- Act on thick ascending tubules (loop). Work by blocking Na/K/2Cl symporter and by increasing Ca excretion.
- Adminisitration can be oral and intravenous.
- Toxic when there is K+ depletion/hypokalemia.
Clonidine
- Antihypertensive drug
- Centrally acting agent (sympathoplegic)
- a2 agonist
- Works presynaptically in order to reduce NE in the brain* —-For mild/moderate HT.
- Sympathoplegic mechanism unknown.
- Toxicity is minimal, but sudden cessation causes high HT.
- Can inhibit insulin secretion
Ganglion Blockers
- antihypertensive drug
- nicotinic cholinoceptor antagonist
- for severe HT (it has a rapid onset).
- It works by blocking the nAChR in the autonomic ganglia. —Its toxicity is intolerable (constipation,..) and therefore it is used rarely. (not very clinically important because they affect the ganglia which affect the sympathetic muscles directed by the ganglia)
Reserpine, guanetidine
- Antihypertensive drug
- Postsympathetic ganglion neuron blocker
- It is rarely used.
- Reserpine works by blocking the reuptake of NA into the vesicles, whereas Guanetidine works by preventing neurotransmitter release.
- Its toxicity is that they are intolerable. (not clinically important because it has a broad effect, even on the CNS)
Prazosin
- Anti-hypertensive drug
- Adrenoreceptor blocker: a1 receptor antagonist
- Important monotherapy if used for mild/moderate HT (a and ß blockers). And ß blockers are used in polypharmacy for moderate/severe HT. Toxicity is mild for a1 blockers (monotherapy).
Propanolol
- Anti-hypertensive drug and myocardial ischemia and antiarrhythmia (Slow AV conduction and prolong PR interval)
- Adrenoreceptor blocker: ß1 receptor antagonist
- Important monotherapy if used for mild/moderate HT (a and ß blockers).
- Used for effort angina and acute coronary syndrome. ———Works by reducing blood pressure and cardiac work.
- Side effects include orthostatic hypotension, tachycardia and headache.
- And ß blockers are used in polypharmacy for moderate/severe HT.
- toxicity is moderate for ß1 blockers (polypharmacy)
Nitroprusside
- Anti-hypertensive drug
- Vasodilator category of drugs
- release of NO causes vasodilatation of arterioles. It is a Nitrovasodilator.
- Can be used for hypertensive emergency.
- Works by activating soluble guanylate cyclase (converts GTP –>cGMP) which reduces Ca voltage channels activity leading to relaxation of vascular smooth muscle.
- Toxicity leads to excessive hypotension and tachycardia.
- Part of Polypharmacy for Severe Hypertension
Diazoxide
- Anti-hypertensive drug
- Vasodilator
- Opening of K+ channels and hyperpolarization.
- Vasodilatation is caused by Opening of K+ channels (agonist) and hyperpolarization of blood vessel, taking away the potential where v-gated Ca channels open up, reducing BP.
- Can be used for hypertensive emergency.
- Toxicity can lead to mild tachycardia.
- Part of Polypharmacy for Severe Hypertension
Verapamil
-Anti-hypertensive drug and myocardial ischemia
-Vasodilator
-blocking L-type Ca channels (voltage- and frequency- dependent block). Works by peripheral vasodilation and reduction of cardiac work.
Used for effort angina and variant angina (prophylactic).
-It is used as a monotherapy for mild/moderate HT.
-Each drug has a distinct binding site. Therefore they can have an additive effect if combined. All three binding sites are located on the same subunit.
-Toxicity due to excessive vasodilation and cardiodepression. toxicity can include orthostatic hypotension, AV block and edema.
-Part of Polypharmacy for Severe Hypertension
Diltiazem
-Anti-hypertensive drug and myocardial ischemia
-Vasodilator
-blocking L-type Ca channels (voltage- and frequency- dependent block). Works by peripheral vasodilation and reduction of cardiac work.
Used for effort angina and variant angina (prophylactic).
-It is used as a monotherapy for mild/moderate HT.
-Each drug has a distinct binding site. Therefore they can have an additive effect if combined. All three binding sites are located on the same subunit.
-Toxicity due to excessive vasodilation and cardiodepression. toxicity can include orthostatic hypotension, AV block and edema.
-Part of Polypharmacy for Severe Hypertension
Nifedipine
- Anti-hypertensive drug and for myocardial ischemia
- Vasodilator
- blocking L-type Ca channels (voltage- and frequency- dependent block). Works by peripheral vasodilation and reduction of cardiac work.
- Used for effort angina and variant angina (prophylactic).
- It is used as a monotherapy for mild/moderate HT.
- Each drug has a distinct binding site. Therefore they can have an additive effect if combined. All three binding sites are located on the same subunit.
- Toxicity due to excessive vasodilation and cardiodepression. toxicity can include orthostatic hypotension, AV block and edema.
- Part of Polypharmacy for Severe Hypertension
Captopril
- Anti-hypertensive drug and congestive heart failure (First line agents (with diuretics) in Heart Failure)
- ACE inhibitors
- Also prevent breaking down of bradykinin –> vasodilatation
- Toxicity leads to cough and severe renal damage in the fetus. It also prevents the break down of bradykinin which is involved in vasodilatation in addition to blockin conversion of agiotensin 1 into angiotensin 2 (active molecule).