TDM Flashcards
Entails analysis, interpretation, and evaluation of drug concentration in serum, plasma, or whole blood samples
THERAPEUTIC DRUG MONITORING
Used to establish maximum benefits with minimal toxic effects for drugs whose correlation with dosage, effect or toxicity is not clear
THERAPEUTIC DRUG MONITORING
T/F
TDM is a routine laboratory test
F
NOT a routine laboratory test: Majority of drugs available in the market have its standard dosage (established)
Assesses drugs with NARROW THERAPEUTIC INDEX
THERAPEUTIC DRUG MONITORING
MAIN PURPOSE of TDM
- Ensure the drug dosage will produce maximal therapeutic benefit
- Identify when the drug is outside the therapeutic range
concentration of drug in the human sample that will produce pharmacologic/therapeutic benefit
Therapeutic range
effect if < TR
inefficacy
effect if > TR
toxicity
therapeutic range of a drug is almost the start of the toxic level (causes adverse effects)
Narrow therapeutic index
dose that provides therapeutic benefits (safe & effective) in most healthy population
STANDARD DOSAGE
T/F
Standard dose is used in diseased state
F
Not utilized in diseased state (diseased patients have alteration in physiologic condition) – can affect the predicted concentration of the standard dose
What must be done during diseased state to fit the individual needs
dosage regimen by performing TDM
FACTORS AFFECTING CIRCULATING CONCENTRATION OF DRUG
Route of Administration
Absorption
Drug Distribution
Free vs Bound Drug
Drug Metabolism
Drug Elimination
considered to achieve maximum therapeutic benefit of the drug
Route of Administration
Most direct and effective route of administration with 100% bioavailability
Intravenous (IV)
most common and least invasive route of administration
Oral (GI absorption)
Route of Administration done by Inhalation or skin absorption (transdermal patch)
Transcutaneous
Route of Administration done by rectal delivery and performed if oral delivery is not possible among infants (not all the time)
Suppository
Routes of Drug Administration based on the effectivity in drug delivery or in bioavailability
IV
IM
SC
Transcutaneous
Suppository
Oral
fraction of administered dose of drug that reaches the site of action or the circulation
Bioavailability
When drugs are absorbed, it can circulate in the blood either as?
free drug or protein-bound drug
active drug which exhibits therapeutic benefit
free / unbound drug
T/F
Only free drugs exhibit therapeutic benefit
F
Some protein-bound drugs may also exhibit therapeutic benefit.
2 fates of circulating drug
- distributed to the site of action (target of the drug) → shows biologic response
- metabolized and eliminated in their metabolite form
Things to consider in Drug Absorption
Formulation of Drug
Active transport
Passive Diffusion
Stomach (acidic)
Small intestine (slightly alkaline)
form of drug that is dissolved before absorption? what form has fast absorption?
Tablet/capsule
Liquid – fast absorption
Absorption intended for dietary constituents
Active transport
Absorption of majority of the drug from the GI tract → bloodstream (no energy required)
Passive Diffusion
Requirement for Passive Diffusion of drugs
drug must be hydrophobic/non-ionized state
Organ that efficiently absorbs weak acid drug
Stomach
Organ that efficiently absorbs weak base drug
Small intestine
T/F
Amount of absorbed drug in GI tract (stomach, intestines) is predictable
T
T/F
Vomiting patients may have orally administered drugs
F
drug must be administered through IM/IV
Ability of drug to leave the circulation depends on their
lipid solubility
Relative proportion of the drug in the circulation and tissue/site of action
Drug Distribution
type of drugs that can cross cell membrane and lipid compartment
Hydrophobic drugs
type of drugs that can cross cell membrane but cannot reach lipid compartment
Polar (non-ionized)
type of drugs that can cross cell membrane at a slow rate
Polar (ionized)
formula of Volume of Distribution (Vd) index
Vd = D/C
what is D in Volume of Distribution (Vd) index formula
IV injected dose of drug (mg/g)
what is C in Volume of Distribution (Vd) index formula
Conc. of drug in the blood (mg/L or g/L)
Vd of Hydrophobic Drugs
↑
Vd of Ionized/Bound Drugs
↓
Acidic drug binds to
albumin
Basic drug binds to
a1-acid glycoprotein
only the free/unbound can interact with its site of action and result in a biologic response
Drug dynamics
T/F
Increased free/unbound drugs in the circulation means that there will be increased therapeutic response.
F
Increased free/unbound drugs in the circulation does not mean that there will be increased therapeutic response – can lead to TOXICITY
T/F
There is a standard percentage/conc. of the absorbed drug that can be free or protein-bound
T
How many protein bound and free absorbed digoxin in circulation
25% protein-bound
75% free
T/F
When there is changes in blood protein content, Digoxin for example with 25% protein-bound may increase >25% due to higher chance to bind to protein
T
Factors that changes Free vs Bound drugs
- Inflammation
- Hepatic disease
- Malignancies
- Nephrotic syndrome
- Pregnancy
- Malignancy
- Malnutrition
Drug Metabolism
First-Pass Metabolism
Pharmacogenomics
All drugs/substances absorbed by GI passes the hepatic portal system (liver) for metabolism before it enters the circulation
First-Pass Metabolism
T/F
Efficacy of some drugs depends on the generation of metabolites
T
Process of parent drug (administered) generated into its metabolites
Biotransformation
Capacity of individual to metabolize drug when there is impaired liver function
reduced
Examines variation (influenced by genes) in hepatic metabolism rates between individuals
Pharmacogenomics
Drug Elimination
Hepatic metabolic processes
Renal filtration
drug elimination wherein liver alters drugs into its metabolites and these metabolites are conjugated to make them water-soluble
Hepatic metabolic processes
drug elimination wherein kidneys filters conjugated metabolites into the urine
Renal filtration
Specimens for TDM
Serum, Plasma, Whole Blood
blood collection tube for serum in TDM
plain tube only
blood collection tube for plasma in TDM
heparinized tube
use of SST [yellow/gold] in TDM may cause? reason?
false ↓
gel separator may absorb some drugs
drugs absorbed by gel separator
phenytoin
phenobarbital
lidocaine
quinidine
carbamazepine
These Ca-binding anticoagulants interfere with drug analysis
EDTA, citrates, oxalates
Method for TDM
HPLC
Immunoassays
GC-MS (gold standard)
single most important factor in TDM
Timing of Blood Collection
lowest conc. of drug measured in the blood
Trough Concentration
what is the timing of collection to determine trough conc.?
collect blood right before administration of next dose
what is the timing of collection to determine peak conc. of orally administered drugs?
1hr after administration (except Digoxin)
what is the timing of collection to determine peak conc. of intravenously administered drugs?
30 mins. after administration
highest conc. of drug measured in the blood
Peak Concentration
determines if the drug already reached the toxicity level
Peak Concentration
exception for determination of peak concentration from oral drugs
Digoxin
collect blood 8-10 hr after initial dose
time required for serum conc. of drug to be decreased/reduced by half
Half-life
Categories of TDM DRUGS
- Cardioactive
- Antibacterial
- Antiepileptic (Anticonvulsant)
- Psychoactive
- Bronchodilator
- Immunosuppressive
- Antineoplastic
Types of Cardioactive drugs
cardiac glycosides
anti-arrhythmic
T/F
All drugs under each categories must undergo TDM
F
*not all drugs under each categories undergo TDM; only selected drugs
EXAMPLES OF CARDIOACTIVE DRUGS
DIGOXIN
QUINIDINE
PROCAINAMIDE
DISOPYRAMIDE
LIDOCAINE
brand name of DIGOXIN
Lanoxin
Protein-bound DIGOXIN
25%
TR of DIGOXIN
0.8-2 ng/ml
Peak conc. of DIGOXIN
2-3 hr
Half-life of DIGOXIN
38 hr
Toxic range of DIGOXIN
> 2-3 ng/ml
manifestation of DIGOXIN toxicity
- Nausea
- Vomiting
- Visual disturbances
- Premature ventricular contraction (PVC)
- Atrioventricular node blockage
DIGOXIN is used as tx for? what is the mechanism?
CHF
inhibit Na-K ATPase pump = ↓ IC K+ = ↑ K+ in circulation = ↑ IC Ca2+ → promote cardiac contractility
digoxin metabolite
Digoxigenin
Timing of Blood Collection for Digoxin
8-10 hr (after administration); correlated with digoxin conc. in tissue
Method for DIGOXIN
IA
brand name/s of QUINIDINE
Quinidex Extentabs
Cardioquin
Quinora
Protein-bound QUINIDINE
70-80%
TR of QUINIDINE
2-5 ug/ml
2 common formulation of QUINIDINE
Quinidine Sulfate
Quinidine Gluconate
formulation of quinidine with complete and rapid GI absorption
Quinidine Sulfate
peak conc. of Quinidine Sulfate
2 hr
quinidine that is slow-release formulation and has a slower absorption
Quinidine Gluconate
peak conc. of Quinidine Gluconate
4-5 hr
half-life of QUINIDINE
6-8 hr
manifestation of QUINIDINE toxicity
- Nausea
- Vomiting
- Abdominal discomfort
- Thrombocytopenia
- Tinnitus
- CV toxicity (PVC)
occur if blood conc. of Quinidine is 2x the upper limit of TR (10 ug/mL)
CV toxicity (PVC)
Naturally occurring drug – extracted from barks of fever tree (Cinchona spp.)
QUINIDINE
QUNIDINE is tx for
cardiac arrhythmia
methods for QUINIDINE
Chromatography, IA
brand name of PROCAINAMIDE
Procanbin
Procan SR
Pronestyl
Protein-bound PROCAINAMIDE
20%
TR of PROCAINAMIDE
4-8 ug/ml
peak conc. of PROCAINAMIDE
1 hr
half-life of PROCAINAMIDE
4 hr
manifestations of PROCAINAMIDE toxicity
- myocardial depression
- arrhythmia
PROCAINAMIDE is a tx for
cardiac arrhythmia
cardioactive drug metabolized in the liver
PROCAINAMIDE
A parent drug; effective form is its metabolite – NAPA
PROCAINAMIDE
method for PROCAINAMIDE
IA
procainamide metabolite
N-acetylprocainamide (NAPA)
inclusions in TOTAL PROCAINAMIDE
conc. of parent drug (procainamide) & conc. of metabolite
(NAPA) as these 2 has same effect
brand name of DISOPYRAMIDE
Norpace
TR of DISOPYRAMIDE
3-7.5 ug/ml
peak conc. of DISOPYRAMIDE
1-2 hr
half-life of DISOPYRAMIDE
7 hr
toxic ranges of DISOPYRAMIDE?
> 4.5 ug/ml
10 ug/ml
Toxic range of DISOPYRAMIDE with anticholinergic effect
> 4.5 ug/ml
Toxic range of DISOPYRAMIDE with cardiac effects
> 10 ug/ml
anticholinergic effects of DISOPYRAMIDE
Dry mouth
Constipation
cardiac effects of DISOPYRAMIDE
Bradycardia – slower than normal heart rate
AV node blockage
A Quinidine substitute – esp. if adverse effects of quinidine is unacceptable
DISOPYRAMIDE
methods for DISOPYRAMIDE
Chromatography, IA
cardioactive drug with TR that is also its toxic range? what is the TR and toxic range that is similar?
DISOPYRAMIDE
> 4.5 ug/ml (within 3-7.5 ug/ml)
TR of LIDOCAINE
1.5-4 ug/ml
Toxic range of LIDOCAINE
4-8 ug/ml
>8 ug/ml
manifestation of LIDOCAINE toxicity if 4-8 ug/ml
CNS depression
manifestation of LIDOCAINE toxicity if >8 ug/ml
seizure, ↓ BP and cardiac output
Corrects ventricular arrhythmia
LIDOCAINE
Prevent ventricular fibrillation
LIDOCAINE
LIDOCAINE is a tx for
AMI
EXAMPLES OF ANTIBACTERIALS
AMINOGLYCOSIDES
TEICOPLANIN
VANCOMYCIN
CHLORAMPHENICOL
Protein-bound AMINOGLYCOSIDES
10%
TR of AMINOGLYCOSIDES
Dependent on
aminoglycosides
used
peak conc. of AMINOGLYCOSIDES
1-2 hr
half-life of AMINOGLYCOSIDES
2-3 hr
toxic range of AMINOGLYCOSIDES
any conc. above TR of aminoglycosides
toxicity of aminoglycosides
Nephrotoxicity
Ototoxicity
toxicity of aminoglycosides with hearing and balance impairment
Ototoxicity
toxicity of aminoglycosides with impairment of PCT function
Nephrotoxicity
REVERSIBLE Nephrotoxicity of Aminoglycosides
- Electrolyte imbalance
- Proteinuria (Albuminuria)
IRREVERSIBLE Nephrotoxicity of Aminoglycosides
(chronic toxicity)
* Tissue Necrosis
* Kidney Failure
antibacterial drugs that are protein synthesis inhibitors
AMINOGLYCOSIDES
CHLORAMPHENICOL
aminoglycosides is effective against
Gram negative bacteria
Examples of aminoglycosides
Gentamicin
Tobramycin
Amikacin
Kanamycin
Methods for aminoglycosides
Chromatography, IA
Administration of aminoglycosides
IV or IM
bioavailability of aminoglycosides
100% (administered IV/IM) –> toxicity is much
faster/common
Protein-bound TEICOPLANIN
90-95%
highly protein bound antibacterial drug
TEICOPLANIN (90-95%)
TR of TEICOPLANIN
10-60 mg/L
20-60 mg/L
TR of TEICOPLANIN used as tx for endocarditis
10-60 mg/L
TR of TEICOPLANIN used as tx for staph. infection
20-60 mg/L
half-life of TEICOPLANIN
70-100 hr
manifestation of TEICOPLANIN toxicity
- Nausea
- Vomiting
- Fever
- Diarrhea
- Mild hearing loss
TEICOPLANIN is a tx for
Methicillin-resistant Staphylococcus aureus (MRSA)
TEICOPLANIN is effective against
Aerobic & anaerobic gram positive cocci and bacilli
antibacterial drug not metabolized by the liver
TEICOPLANIN
Administration of TEICOPLANIN
IV or IM
brand name of VANCOMYCIN
Vancocin HCl
protein-bound VANCOMYCIN
55%
TR of VANCOMYCIN
5-10 ug/mL
peak conc. of VANCOMYCIN
1 hr
half-life of VANCOMYCIN
4-6 hr
antibacterial drug wherein TR is the toxic range? what is the toxic range?
VANCOMYCIN
10 ug/mL
common toxic effect of vancomycin characterized by erythemic flushing of extremities
Red-man syndrome
toxic range of vancomycin that exhibits nephrotoxicity
> 10 ug/ml
toxic range of vancomycin that exhibits ototoxicity
> 40 ug/ml
vancomycin is tx for
Gram positive cocci and bacilli
Cell wall inhibitor; kills microbes by destruction or inhibition of cell wall synthesis
vancomycin
administration of vancomycin
IV
manifestation of CHLORAMPHENICOL toxicity
Blood dyscrasia (aplastic anemia)
CHLORAMPHENICOL is a tx for
Gram negative bacteria
antibacterial drug effective against gram negative bacteria
AMINOGLYCOSIDES
CHLORAMPHENICOL
antibacterial drug effective against gram positive cocci and bacilli
TEICOPLANIN
VANCOMYCIN
Examples of PSYCHOACTIVE DRUGS (Anti-psychotic drugs)
LITHIUM
TRICYCLIC ANTIDEPRESSANT (TCA)
CLOZAPINE
OLANZAPINE
brand name/s of LITHIUM
Eskalith
Lithobid
Protein-bound lithium
Lithium salts, so it doesn’t bind to protein
TR of LITHIUM
0.5-1.2 mmol/l
peak conc. of LITHIUM
2-4 hr
half-life of LITHIUM
10-35 hr
toxic ranges of LITHIUM
1.5-2 mmol/L
>2 mmol/L
manifestation of LITHIUM toxicity if 1.5-2 mmol/L
apathy
lethargy
speech difficulties
muscle weakness
manifestation of LITHIUM toxicity if >2 mmol/L
muscle rigidity
seizures
coma
LITHIUM uses this that does not bind to proteins
lithium salts
Mood-altering drugs
LITHIUM
LITHIUM is a tx for
recurrent depression
bipolar disorder
Administration of LITHIUM
Oral (completely and rapidly absorbed by GI)
protein-bound TCA
85-95%
2 forms of TCA
Amitriptyline
Imipramine
TR of Amitriptyline (a TCA)
120-150 ng/ml
TR of Imipramine (a TCA)
150-300 ng/ml
peak conc. of TCA
2-12 hr
manifestation of TCA toxicity when there is slight increase
drowsiness
constipation
blurred vision
memory loss
manifestation of TCA toxicity at higher levels
seizures
cardiac arrhythmia
unconsciousness
TCA includes?
amitriptyline
imipramine
doxepin
TCA is a tx for
depression
insomnia
extreme apathy
loss of libido
Administration of TCA
oral
antipsychotic drug that is metabolized into its metabolize forms? what are these?
TCA
Imipramine → desipramine
Amitriptyline → nortriptyline
Therapeutic effects of this drug is not seen for the first 2-4 weeks after initiation of therapy; hence, effects of TCAs only occur after 4 weeks
TCA
brand name of CLOZAPINE
Clozaril
FazaClo
protein-bound CLOZAPINE
97%
TR of CLOZAPINE
350-420 ng/ml
peak conc. of CLOZAPINE
2 hr
half-life of CLOZAPINE
8-16 hr
manifestation of CLOZAPINE toxicity
seizures
CLOZAPINE is a tx for
Treatment-refractory schizophrenia
brand name of OLANZAPINE
Zyprexa
protein-bound OLANZAPINE
93%
TR of OLANZAPINE
20-50 ng/ml
peak conc. of OLANZAPINE
5-8 hr
half-life of OLANZAPINE
21-54 hr
Thienobenzodiazepine derivative
OLANZAPINE
OLANZAPINE is a tx for
schizophrenia
acute manic episodes
bipolar disorders (recurrent)
Administration of OLANZAPINE
Oral
IM (fast-acting formulation)
EXAMPLES OF IMMUNOSUPPRESIVE DRUGS
CYCLOSPORINE
TACROLIMUS (FK-506)
SIROLIMUS (RAPAMYCIN)
MYCOPHENOLIC ACID (MPA)
Cyclic polypeptide with potent immunosuppressive activity
CYCLOSPORINE
function is to suppress graft-vs-host rejection (heterotopic transplanted organ) → piggyback transplant
CYCLOSPORINE
specimen of choice for CYCLOSPORINE? reason?
whole blood
cyclosporine is sequestered inside the cell, including RBCs
BRAND NAME/S of CYCLOSPORINE
Gengraf
Neoral
Sandimmune
Protein-bound CYCLOSPORINE
> 98%
TR of CYCLOSPORINE
Depends on transplanted organ
TR of CYCLOSPORINE if the transplanted organs are – liver, heart, pancreas
200-350 ng/m
TR of CYCLOSPORINE if the transplanted organ is kidneys
100-300 ng/ml
peak conc. of CYCLOSPORINE
1-6 hr
toxic range of CYCLOSPORINE
350-400 ng/ml
toxicity of CYCLOSPORINE
*nephrotoxic
- Renal tubular dysfunction
- Glomerular dysfunction
heart, liver, pancreas; attaching donor’s organ to the original patient’s organ
Piggyback transplant
brand name/s of TACROLIMUS
Hecoria
Envarsus
Prograf
Astagraf
protein-bound TACROLIMUS
> 98%
TR of TACROLIMUS
10-15 ng/ml
aka FK-506
TACROLIMUS
toxicity of TACROLIMUS
Nephrotoxicity
Thrombus formation
100x more potent than cyclosporine
TACROLIMUS
function is to suppress transplant rejection, and graft-vs-host disease
TACROLIUMUS
specimen of choice for TACROLIMUS
whole blood
SIROLIMUS is aka
RAPAMYCIN
brand name of SIROLIMUS
Rapamune
protein-bound SIROLIMUS
92% bound to LPP
TR of SIROLIMUS if administered w/ cyclosporine
4-12 ug/L
TR of SIROLIMUS if – if cyclosporine is not used/discontinued
12-20 ug/L
toxicity of SIROLIMUS
Blood dyscrasia (anemia, leukopenia, and thrombocytopenia → aplastic anemia)
Hyperlipidemia
Antifungal agent with immunosuppressive activity
SIROLIMUS
a prophylactic drug to prevent graft rejection before kidney transplant
SIROLIMUS
Specimen of choice for SIROLIMUS
Whole Blood
drugs used in conjunction with cyclosporine or tacrolimus
SIROLIMUS
MYCOPHENOLIC ACID
brand name of MPA
Myfortic
Protein-bound MPA
95%
toxicity of MPA
Nausea
Vomiting
Diarrhea
Abdominal pain
Prodrug of mycophenolate mofetil
MPA
a Lymphocyte proliferation inhibitor and immunosuppressive drug
MPA
supplemental therapy with cyclosporine & tacrolimus esp. if the patient is a renal transplant patient
MPA
brand name/s of METHOTREXATE
Otrexup
Rasuvo
toxicity of METHOTREXATE
Cytotoxicity
administered to lessen and ensure nonlethal cytotoxicity produced by methotrexate
Leucovorin (Leucovorin rescue)
Destroys neoplastic cells by inhibiting DNA synthesis
METHOTREXATE
DNA synthesis inhibitor
METHOTREXATE
Can both affect normal and neoplastic cells since they both have DNA (but neoplastic cells are more susceptible)
METHOTREXATE
METHOTREXATE is a tx for
Psoriasis
brand name/s of THEOPHYLLINE
Theo-Dur
Thea-24
Uniphyl
Protein-bound THEOPHYLLINE
50-60% (usually bound to ALBUMIN)
TR of THEOPHYLLINE
10-20 mg/L
formulation of THEOPHYLLINE with 1-2 hr peak conc.
rapid-release formulation
formulation of THEOPHYLLINE with 4-8 hr peak conc.
modified-release formulation
toxicity of THEOPHYLLINE if >20 ug/ml
nausea, vomiting, diarrhea
toxicity of THEOPHYLLINE if >30 ug/ml
cardiac arrhythmia, seizures
THEOPHYLLINE is a tx for
asthma
stable COPD
a bronchodilator
THEOPHYLLINE
an anti-neoplastic drug
METHOTREXATE
Types of seizures
Grand mal seizure/Tonic–Clonic
Complex Partial Seizure
Petit mal/ Absent/ Starting Seizure
Types of seizure that lasts for >5mins
Tonic–Clonic (Grand mal seizure)
Types of seizure that arises from one side of brain
Complex Partial Seizure
Types of seizure that black out for a minute
Petit mal/ Absent/ Starting Seizure
brand name/s of PHENOBARBITAL
Luminal
Solfoton
brand name/s of PHENYTOIN
Dilantin
brand name/s of VALPROIC ACID
Depakote
Depakene
brand name/s of CARBAMAZEPINE
Tegretol
brand name/s of ETHOSUXIMIDE
Zarontin
brand name/s of FELBAMATE
Felbatol
brand name/s of GABAPENTIN
Neurontin
brand name/s of LAMOTRIGINE
Lamictal
brand name/s of OXCARBAZEPINE
Trileptal
brand name/s of TIAGABINE
Gabitril
brand name/s of TOPIRAMATE
Topamax
brand name/s of ZONISAMIDE
Zonegran
protein-bound PHENOBARBITAL
50%
protein-bound PHENYTOIN (Diphenylhydantoin)
87-97%
protein-bound VALPROIC ACID
93%
protein-bound CARBAMAZEPINE
70-80%
protein-bound ETHOSUXIMIDE
<5%
protein-bound FELBAMATE
30%
protein-bound GABAPENTIN
Do not bind to protein
protein-bound LAMOTRIGINE
55%
protein-bound OXCARBAZEPINE
40%
protein-bound TIAGABINE
96%
protein-bound TOPIRAMATE
15%
protein-bound ZONISAMIDE
60%
toxicity of PHENOBARBITAL
Drowsiness
Fatigue
Depression
Reduced mental capacity
Slow-acting barbiturate
PHENOBARBITAL
tx for all types of seizures except petit mal
PHENOBARBITAL
administration of PHENOBARBITAL
oral; slow GI absorption but complete
inactive proform of phenobarbital
Primidone
Primidone is a tx for
Grand mal seizure
Readily absorbed by GI; undergo first-pass metabolism to form PHENOBARBITAL
Primidone
toxicity of PHENYTOIN
Seizures
Ataxia – difficulty in balanced walking
Coma
Vit D deficiency
Seizures
PHENYTOIN is a tx for
tonic-clonic seizure
proform of phenytoin; IM drug
Fosphenytoin
rapidly absorbed within 75 mins after administration → already metabolized
Fosphenytoin
Conditions when protein-binding is ↓
Anemia
Hypoalbuminemia
Coadministration of same binding properties as phenytoin
toxic value of VALPROIC ACID
> 120 ug/mL
most common toxicity of VALPROIC ACID
- Nausea
- Lethargy
- Weight gain
more serious toxicity of VALPROIC ACID (>200 ug/mL)
Pancreatitis
Hyperammonemia
Hallucinations
VALPROIC ACID is a tx for
petit mal seizure
Inhibit metabolism of other anti-epileptic drugs
VALPROIC ACID
CARBAMAZEPINE toxicity
Ataxia
Leukopenia
Seizures
Aplastic anemia
CARBAMAZEPINE toxicity if >15 ng/mL
Aplastic anemia
usually has RARE TOXICITY, often tolerable, self-limiting
ETHOSUXIMIDE
CARBAMAZEPINE is a tx for
seizure and facial pain
ETHOSUXIMIDE is a tx for
petit mal seizure
PRIMIDONE toxicity
Anemia
Ataxia
Nausea
PRIMIDONE is a tx for
tonic-clonic and complex partial seizure
FELBAMATE toxicity
Fatal aplastic anemia
Hepatic failure
FELBAMATE is a tx for
Mixed-seizure disorders (children)
Lennox-Gastaut syndrome
Refractory epilepsy (adults)
administration of FELBAMATE
Oral (most common; almost complete absorption of felbamate in GI tract)
GABAPENTIN toxicity
*mild
* Fatigue
* Ataxia
* Dizziness
* Weight gain
GABAPENTIN is a tx for
AED for patients with
o Liver disease
o Acute Intermittent Porphyria (w/ partial onset seizures)
GABAPENTIN administration
Oral (60% bioavailability)
T/F
Gabapentin is metabolized by the liver
F
LAMOTRIGINE toxicity
Usually evident if given with valproic acid as it can inhibit metabolism of other AED
* dizziness
* GI disturbances
* rashes
LAMOTRIGINE is a tx for
partial or generalized tissues
OXCARBAZEPINE toxicity
Similar with carbamazepine
OXCARBAZEPINE is a tx for
partial seizures
tonic-clonic seizures
OXCARBAZEPINE Administration
oral (immediately into licarbazepine)
metabolite of OXCARBAZEPINE
Licarbazepine
TIAGABINE toxicity
confusion
stuttering
mild sedation
PARESTHESIA
TIAGABINE is a tx for
partial seizures
has toxicity of change of taste with particular foods (diet coke and beet)
TOPIRAMATE
TOPIRAMATE toxicity
change of taste with particular foods (diet coke and beer)
“pins and needles” sensation in extremities
TOPIRAMATE administration
Oral (almost completely absorbed; almost 100% bioavailability)
ZONISAMIDE toxicity
breathing difficulty
low BP
slow heart rate
loss of consciousness
an anticonvulsant
ZONISAMIDE
ZONISAMIDE is a tx for
partial and generalized seizure
administration of ZONISAMIDE
Oral
