Pharm Pearls

Question 1

Fluvoxamine is a strong inhibitor of which CYP 450 enzyme?

This could cause toxicity of which asthma drug?

Answer 1

1A2

Theophylline

Question 2

Is lithium safe during pregnancy?

Answer 2

Not preferred, risk of cardiac malformations including Ebstein’s anomaly

Question 3

Is Depakote safe during pregnancy?

Answer 3

ValproATE the folATE

Neural tube defects

Question 4

Dosing consideration when combining Depakote with lamotrigine

Answer 4

Lamotrigine dose must be decreased by 50%

Question 5

Lamotrigine dosing with carbamazepine, phenobarbital, phenytoin, primidone

Answer 5

Must increase lamotrigine dose by 50% as other drugs are inducers

Question 6

Lamotrigine dosing Initiation schedule for monotherapy

After how many days of missed doses should lamotrigine dosing go back to beginning?

Answer 6

25 mg daily x 2 weeks
50 mg daily x 2 weeks
Then 100 mg daily on week 5, up to max dose of 200 mg daily starting week 6

If doses are missed 4-5 or more days, must restart again at 25 mg and go through entire schedule

Question 7

Do not start lamotrigine therapy within two weeks of virus To reduce risk of rash

Answer 7

Viral infection, rash, vaccination. Also avoid new medications, foods, or products during the first three months to decrease risk of unrelated rash. 10% of Patients develop non-severe rash

Question 8

What is the lithium monitoring schedule

Answer 8

Every 1 to 2 weeks until desired serum concentration has achieved

Then every 2 to 3 months for the first six months

Then Once stabilized every 6 to 12 months

Question 9

Duloxetine (Cymbalta)

INHIBITS

Answer 9

1A2

2D6

Question 10

Causes of SIADH (results in hyponatremia)

Symptoms

Answer 10

Carbamazepine
Amitriptyline, morphine, SSRIs

Hypothyroidism

Irritability, nausea, vomiting, muscle weakness, confusion, hallucinations, seizures, stupor, coma

Question 11

Lithium monitoring

Answer 11

Baseline creatinine TSH and CBC pregnancy test. Steady state achieved after five days. check Li level 12 hours after last dose. once stable check Li every three months and TSH and creatinine every six months.

Ebstein’s anomaly

Therapeutic between 0.6-1.2

Question 12

Depakote monitoring

Answer 12

Blocks VSSC

Baseline LFT, CBC, coagulation studies, Hcg. Monitor multiple times during first few months, then 6-12 months
Start folic acid supplement and women

Monitoring steady state achieved after 4 to 5 days check valproic acid level 12 hours after last last dose and repeat CBC and LFTs

Starting dose 1000 mg per day for acute mania

Target level between 50 to 100

Potentially fatal hepatotoxicity and pancreatitis, and cardiac fatal in OD

Question 13

Carbamazepine

First line agent for acute mania and mania prophylaxis. Indicated for rapid cyclers and mixed patients

Answer 13

Baseline LFT, CBC, EKG

Steady state achieved after five days check 12 hours after last dose and repeat CBC and LFTs

Target level 4 to 12

Check level After about a month because it induces it’s own metabolism

Question 14

Factors predicting a positive response to valproic acid

Answer 14

Rapid cycling patients, female more than male, Comorbid substance issues, mixed pts, and pts with comorbid anxiety is disorders

Better tolerated than lithium

Question 15

Carbamazepine

Answer 15

Rash

AV conduction delays
Aplastic anemia and Agranulocytosis

CYP3A4 inducer

Risk of SJS

Monitor CBC, LFT, can cause liver damage, can alter warfarin levels, Spina bifida risk with pregnancy

Question 16

Lamotrigine

Answer 16

Also used for neuropathic/chronic pain

RASH—->SJS

Baseline LFT

If medicine not taken for five days or more, must restart titration at 25 mg daily times two weeks, then 50 mg daily times two weeks, ECT

Question 17

Three causes of SJS

Answer 17

Lamotrigine, carbamazepine, valproic acid

Question 18

What happens when mirtazapine is given with clonidine?

Answer 18

They cancel each other out

Mirtazapine’s actions on alpha 2 adrenergic receptors (as an antagonist) cause an increase in NE

Clonidine Is an alpha 2 agonist

Question 19

What can be used to treat the hypersalivation and dysphasia caused by clozapine?

Answer 19

Clonidine patch

Question 20

Which class of anti-depressants is most effective in preventing migraines?

Which class of anti-depressants can worsen migraines?

Answer 20

SNRIs Such as venlafaxine have been found to be effective in preventing migraine

SSRI drugs may worsen migraine

Question 21

What drug when added to Lamictal increases the risk of rash?

Answer 21

Valproate

Question 22

If a patient develops a rash while taking Lamictal within what periods of time is a drug rash unlikely?

Answer 22

During the first five days of Lamictal treatment and after 8 to 12 weeks of treatment

Approximately 10% of patients will develop a rash, but these rashes are benign

Risk of serious rash is less than 1%

Question 23

Invega vs Abilify LAI

Answer 23

Invega is better for patients hearing voices

Abilify better in the context of bipolar disorder

Question 24

What is the antidote for serotonin in serotonin syndrome and what drugs should be avoided?

Answer 24

The antidote is cyproheptadine. Benzodiazepines may be helpful as supportive care.

Avoid dantrolene, bromocriptine, and propranolol

Question 25

What is the antidote in tricyclic antidepressant overdose?

Answer 25

Sodium bicarbonate

Question 26

Signs and symptoms of B12 deficiency

Answer 26

Elevated homocystine, elevated MMA (Methylmalonic acid) maybe present in low normal B12 levels, can be an early sign of B12 deficiency. B12 deficiency causes a macrocytic anemia

Symptoms include impaired memory, irritability, depression, dementia, rarely psychosis, paresthesias, peripheral neuropathy

Oral supplementation preferred even in the case of lack of intrinsic factor

Question 27

What is the effect of combining chamomile with warfarin?

Answer 27

Increased bleeding risk

Question 28

Major risk of using kava kava for anxiety and insomnia

Answer 28

Liver damage

Question 29

Which SSRI carries the highest risk for QT prolongation?

Answer 29

Citalopram

Question 30

Which two medication’s are the only FDA approved treatments for PTSD?

Answer 30

Sertraline, paroxetine

Question 31

Which Alzheimer’s medication is approved to treat all stages of Alzheimer’s disease?

Answer 31

Donepezil does it All (Aricept)

Question 32

What is the effect of smoking on olanzapine drug levels?

Answer 32

Smoking reduces olanzapine levels.