Random 3 Flashcards
Carbamazepine
Reference Range: 4-12
SJS Risk: HLA*B 1502, Asians, highest risk within first 8 weeks of therapy
Drug of choice for trigeminal neuralgia
Can worsen absence seizures
Drugs of choice for absence seizures
Ethosuxmide
Valproate
Phenytoin
Reference range: 10-20, must be corrected in renal (?) due to high albumin binding
ADE = gingival hyperplasia
If pregnant, may continue but must supplement with high-dose folic acid
Max infusion rate 50mg/min, filter with 0.22 micron during administration due to risk of precipitation, only dilute in NS and use continue cardiac monitoring. Do NOT give IM.
Propofol
Max infusion rate 50 mcg/kg/minute - risk of infusion syndrome (PRIS - metabolic acidosis)
ADE = triglycerides, risk of hypotension
IV Lorazepam for sedation
Risk of propylene glycol toxicity - at high risk if osmol gap is > 10-12, or if infusion > 5 mg/hr for > 48 horus
Anion Gap
= Na - (Cl + HCO3)
Normal is 6-12
If hypoalbuminemia, reduction in anion gap for every 1 less than 4.
SEM equation
SEM = SD / sq root of N
CI is 1.96*SEM (95% confidence, 2 SD’s)
Type I error
alpha, rejecting the null when there is no association. P-value 0.05% – 5% of the time we will state there is significant when there is not.
Type II error
beta, accepting the null when there actually is an association. Occurs if the study does not have enough power.
Increasing the power allows you to reduce risk of type 2 error, as it can help to detect smaller differences between groups.
Prevalence vs. Incidence
Prevalence - measures current cases at a given time
Incidence - probability of developing a disease (number of new cases) / those at risk for developing the dx
NNT
1/ARR –> only calculate if statistically significant
Sensitivity vs. Specificity
Sensitivity = true positives Specificity = true negatives
Positive predictive value = True positives / total identified positives
RR vs. OR calculations
RR: (exposure +/total exposure)/(no exposure +/total no exposure) goes from left to right
OR: (dx in exposed/dx non exposed)/(no dx in exposed/no dx non exposed) goes from top to bottom
Relative Risk Reduction/Increase = 1-RR
If OR/RR 0.75 –> 25% reduction in the risk or odds. If 1.5 –> 1.5 times the risk or odds.
CAP Tx:
- Outpatient
- Inpatient
Outpatient:
Amoxicillin, doxycyline, or macrolide
Inpt: Resp FQ (moxi, levo, gemi) or beta lactam + macrolide
If risk factors (COPD, DM) give resp FQ
HAP / VAP Tx
Occurs > 48 hours post admission
Single agent: cefepime, Zosyn, levoflox x 7 days
If IV abx in 90 days, high risk mortality, give 2 antipseudo (beta lactam/aminoglycosides OR FQ/aztreonam)
Add on MRSA if high risk VAP (vanco)
G6PD Deficiency drugs to avoid
Nitrofurantoin Bactrim Rasburicase Primaquine Dapsone
CYP2C9
Warfarin (also VKORC1), factors 2/7/9/10. S isomer»_space; R isomer
Phenytoin
CYP2C19
Clopidogrel (omeprazole)
Voriconazole
HLAB5701
HLAB5801
HLAB*1502
HLAB5701 Abacavir
HLAB5801 allopurinol
HLAB*1502 phenytoin, carbamazepine
High risk of hypersensitivity reactions!
Phase I vs. Phase II
Phase I = CYP3A4 metabolism
Phase II = UGT, NAT - makes drug more hydrophillic
Zero-order elimination vs. first-order elimination
Zero-order, independent of drug concentration (ASA, ethanol, phenytoin)
First-order - concentration dependent, exponential (half-lives, 4-5 t/12)
Therapeutic Index
Narrow TI - poor safety profile
TI = lethal dose in 50% of patients / therapeutic dose in 50% of patients
TI > 10 –> good safety profile.
Empiric Tx for Meningtitis
Neonates = amp + gent
Adults/Kids = ceftriaxone + vanco
Add on ampicillin if age > 50, age < 2 yoa, or immunosuppressed.
Can add corticosteroid before or at first dose to reduce mortality
Chemo prophylaxis for N.meningitidies with rifampin 600 mg BID for 4 days or cipro 500 mg once
Tx 1-2 weeks. Listeria give for 3 weeks.
Endocarditis
Native Value:
Strep = PNC G or ceftriaxone +/- gent
Staph = Naph, cefazolin, vanco if PCN allergy
Prosthetic valve - as above + gent or rifampin and extend duration > 6 weeks
Tx = 4-6 weeks.
Can use dapto for MRSA in native valve only
