1 / 15
NRNP 6675 FINAL EXAM LAST EXAM 2023
- The 1/2 life of lithium is about ANS 24 hours
- Fluoxetine is the SSRI with the WD risk ANS lowest due to long half
life
- What antipsychotics are good for pts who miss doses of their meds ANS
An- tipsychotics with long half-lives:
1. Cariprazine(Vrylar): (2-4 days-active metabolites up to 3 weeks)
- Abilify (3 days)
- Brexipiprazole (4 days)
- Pimozide (4-5 days)
- Pimavanserin (2 days, active metabolites 8 days)
- Disulfiram's alcohol interactions persist for up to how long after the med-
ication is stopped ANS LONG Half life--2-3 days
persist up to 2 weeks following stopping
- What is the only TCA with a long half life ANS Protriptyline (Vivactil) 1 / 4
2 / 15
- Most psychotropics have a medium range 1/2 life of approx ANS 24 hours
- what does "steady state" mean in relation to 1/2 life ANS steady state
means that you are eliminating the drug at the same overall rate that you are ingesting it
- Lithium reaches its 'steady state' when ANS 5 half lives
example:
Day 1: Start pt on Lithium 600 mg daily
Day 2: (24 hours later) the amount left in his body is 300 mg (day 2 min) because 24 hours has passed--one 1/2 life--therefore the pt has excreted 1/2 of the initial amount.THEN the pt takes his 2nd dose of 600 mg on DAY 2-resulting in a max dose of 900 (300 mg left in body + 600 mg of 2nd dose).DAY 3: starts off with 450 mg (1/2 of the 900 mg in pt's system) and after taking the day 3 600 mg dose, the pt now has a total of 1050 mg.
- Due to the steady state of Lithium, when do we draw a blood level ANS 5
half lives
if you check any earlier, the trough level will underestimate the actual level the pt is on after achieving steady state
- / 4
3 / 15
- Fluoxetine has a half life of about ANS 2 weeks 1/2
life take 2.5 months to achieve steady state 3 / 4
4 / 15
- Most psychotropic medications operate in this fashion ANS "when you
double the dose, the serum dose doubles."
*minus three SRIs and three anticonvulsants (Fluoxetine, fluvoxamine, paxil, gabapentin, valproate and carbamazepine)
- induces it's own metabolism, hastening excretion and short-
ening it's half life: ANS A. Carbamazepine (Tegretol)
*this effect begins to "rev up" after 2-4 weeks--which is why a carbamazepine level is so important on obtaining 1-2 months after starting Tegretol.
- Carbamazepine (Tegretol) level should be checked how soon after start-
ing to take this med ANS 1-2 months due to Tegretol inducing it's own metabolism, hastening excretion and shortening it's half life.
- has trouble getting a "serum" level because it binds to proteins
that render it therapeutically inactive ANS A. Valproate Acid (Depakote)
-this is particularly true at the lower levels (eg. <50 mcg/mL), so you can expect dose changes to make a more dramatic difference when the pt's depakote level is in the higher range
- / 4