THERAPEUTIC DRUG MONITORING Flashcards
Bioavailability of intravenous administration
100%
Bioavailability of oral administration
70%
Weak acids are absorbed in the…
Stomach
Weak bases are absorbed in the…
Intestine
Is the release of the drug
Liberation
The transport of drug from the site of administration to the blood
Absorption
Refers to the delivery of the drug to the tissue
Distribution
The process of chemical modification of the drug by the cells
Metabolism
The process by which the drug and its metabolites are excreted from the body
Excretion
Most drugs are absorbed by passive diffusion. At what state should the drug be in?
A. Hydrophilic
B. Hydrophobic
C. Ionized
D. Anxious
B. Hydrophobic
4 factors affecting absorption
pH
Presence of food and other drugs
Changes in intestinal movement
Inflammation
The location where the drugs are effective are in the…
A. Body tissues
B. Blood
C. Intestine
D. Liver
A. Body tissues
Drugs are effective in the body tissues, not generally in the blood
Drugs have higher concentration in _______ than in ________
A. Blood, tissues
B. Tissues, blood
B. Tissues, blood
Refers to the relationship between tissue and blood levels
Distribution space
True or false
A large distribution space indicates that much of the drug moves into the tissues than stays in the circulation
Truly
Where does the conversion of a parent drug to its metabolites happen?
Liver (extramitochondrial microsomal system of the hepatocytes-cytochrome P450 enzymes)
The fraction of the dose that reaches the blood
Bioavailable fraction
Represents the dilution of the drug after it has been distributed in the body
Vd of a drug
It is used to estimate the peak drug blood level expected after a loading dose is given. It is the principal determinant of dose
Vd of a drug
Metabolism wherein the drugs that are transported to the liver lost a fraction of its bioavailability before the drug reaches the general circulation
First-pass hepatic metabolism
Represents the linear relationship between the amount of drug eliminated per hour and the blood level of a drug
First-order elimination
The time to reach the steady-state or average concentration
Half-life
The biochemical pathway responsible for the greatest portion of drug metabolism
Mixed function oxidase (MFO) system
The relationship between the drug concentration at the target site and response of the tissues
Pharmacodynamics
Refers to the study of genes that affect the performance of a drug in an individual
Pharmacogenomics
The mathematical expression of the relationship between drug dose and drug blood level
Pharmacokinetics
The ratio between the minimum toxic and the maximum therapeutic serum concentration
Therapeutic index
The difference between highest and lowest effective dosages
Therapeutic range
The lowest concentration of a drug obtained in the dosing interval
Trough concentration
Enumerate the cardioactive drugs
“Ventricles Produce Pulses Like A Queen Drunk Dances”
Verapamil
Procainamide (Pronestyl)
Propanolol
Lidocaine (Xylocaine)
Amiodarone (Cordarone)
Quinidine
Digoxin
Disopyramide
Enumerate the antibiotics
“Amystery Van Captures”
Aminoglycosides (gentamycin, tobramycin, amikacin, kanamycin, neomycin, streptomycin)
Vancomycin
Chloramphenicol
Enumerate the antiepileptic drugs
“PP Very Choosy, Eats Gun To Look Fierce”
Phenobarbital
Phenytoin (Dilatin)
Valproic acid (Depakene)
Carbamezipine (Tegretol)
Ethosuximide (Zarontin)
Gabapentin (Neurontin)
Topiramate
Lamotrigine (Lamictal)
Felbamate
Enumerate the psychoactive drugs
“Lit Trees = Fire”
Lithium
Tricyclic antidepressants (TCA)
Fluoxetine
Enumerate the bronchodilator drugs
Theophylline
Enumerate the immunosuppressive drugs
Cyclosporine
Tacrolimus
Rapamycin
Mycophenolate mofetil
Leflunomide
Enumerate the antineoplastic drugs
“BM”
Busulfan
Methotrexate
Enumerate the anti-inflammatory/analgesics
“ISA”
Ibuprofen
Salicylates/aspirin (Acetylsalicylic acid)
Acetaminophen (Tylenol)
It blocks the action of dopamine and serotonin in the limbic system; used in the treatment of schizophrenia
Neuroleptics (antipsychotic major tranquilizers)
Classification of cardioactive drugs:
Rapid sodium channel blockers
Class I
Classification of cardioactive drugs:
Beta receptor blockers
Class II
Classification of cardioactive drugs:
K+ channel blockers
Class III
Classification of cardioactive drugs:
Calcium channel blockers
Class IV
Enumerate the class I cardioactive drugs
Quinidine
Procainamide
Lidocaine
Enumerate the class II cardioactive drugs
Propanolol
Enumerate the class III cardioactive drugs
Amiodarone
Enumerate the class IV cardioactive drugs
Verapamil
Treatment for atrial arrhythmias and congestive heart failure
Digoxin
Its therapeutic actions and toxicities can be influenced by serum electrolytes: it inhibits membrane Na-K-ATPase, thus it decreases K and Mg, and increases Ca (cardiac contractilty-inotropic effect)
Digoxin
Hyperthyroid individuals are resistant to this drug
Digoxin
Used to correct ventricular arrhythmia and for treatment of AMI
It can be used as a local anaesthetic
Lidocaine
This drug isn’t administered orally due to almost complete hepatic removal of the absorbed drug
Lidocaine
Naturally occurring drug for the treatment of arrhythmia
Quinidine
It is used to treat ventricular arrythmia
Its toxic effects includes reversible lupus-like syndrome (ANA), nephrotic syndrome, and urticaria
Procainamide
Used to treat cardiac arrhythmias; used as a substitute for quinidine
Disopyramide
This drug has anticholinergic effects which include dry mouth and constipation
Disopyramide
Used in the treatment of thyrotoxicosis; suppresses the conversion of T3 to T4
Propanolol
Blocks potassium channels in the cardiac muscle; use for treatment of ventricular arrhythmias
Amiodarone
It is an iodine-containing drug which can cause hyperthyroidism or hypothyroidism
Amiodarone
Treatment of angina, hypertension, and supraventricular arrhythmias
Verapamil
Used for treatment of gram-negative bacterial infections
Aminoglycosides
Toxic level:
It may cause damage to the 8th cranial nerve at toxic levels (hearing loss)
Aminoglycosides
An antibiotic that requires trough and peak measurements
Aminoglycosides
A glycopeptide effective against gram-positive cocci and bacilli
Vancomycin
Its toxic side effects occur in the therapeutic range; causes red-man syndrome, nephrotoxicity and ototoxicity
Vancomycin
This drug distributes to all tissues, and concentrates in the CSF
Chloramphenicol
A long acting barbiturate that controls grand mal tonic-clonic seizure and focal epileptic; not used for petit mal
Phenobarbital
Used for treating withdrawal symptoms in infants whose mothers are addicted to opiate or barbiturate
Phenobarbital
Used to treat cases of congenital hyperbilirubinemia; enhances bilirubin metabolism
Phenobarbital
Controls seizures (tonic-clonic, simple partial seizures); a short term prophylactic agent in brain injury
It is not used for petit mal or atomic seizures
Phenytoin
Used for treatment of petit mal, atomic seizure, and grand mal
Valproic acid
This drug is highly protein bound (93%)
Valproic acid
A tricyclic compound related to imipramine. It is effective for grand mal seizures and treating seizures accompanied by pain; it has antineuralgic action
Carbamazepine
Can cause idiosyncratic effects: rashes, leukopenia, nausea, vertigo, febrile reactions
Carbamazepine
DOC for controlling petit mal
Ethosuximide
Chemically similar to neurotransmitter gamma aminobutyric acid
It is used for partial seizures; for adjunctive therapy
Gabapentrine
Drugs used for adjunctive therapy for partial seizures
Gabapentin
Topiramate
Lamotrigine
Treatment for manic-depressive illness (bipolar disorders) and is the DOC for the prevention of chronic cluster headache
Lithium
Inhibits thyroid hormone synthesis and release by the inhibition of iodine uptake
Lithium
Inhibits the effect of ADH on the kidney
Lithium
Demeclocycline
Treatment for depression, insomnia, extreme apathy and loss of libido
Tricyclic antidepressants (TCAs)
Major metabolite of TCA
Desipramine
Blocks the reuptake of serotonin in central serotonergic pathways
Fluoxetine
Treatment for OCD
Fluoxetine
It belongs to the methylated xanthine class
Its action is specific to the relaxation of bronchial smooth muscle
Theophylline
It is used in the treatment of asthma and chronic obstructive pulmonary disease
Theophylline
Drug for primary apnea prematurity (absence of respiratory effort in newborn infants)
Theophylline
This drug crosses the placenta and may be teratogenic in pregnant females
Theophylline
Used to prevent rejection of allogenic organ transplants by inhibiting the cellular immune response by blocking the production of IL-2
Cyclosporine
Used for suppressing acute graft-versus-host disease (GVHD)
Cyclosporine
A macrolide lactone antibiotic that is 100x more powerful than cyclosporine
Tacrolimus
This drug is elevated in the presence of cholestasis
Tacrolimus
Similar to tacrolimus; major side effects are lipid abnormalities and thrombocytopenia
Rapamycin
Decreases renal allograft rejection
Mycophenolate mofetil
Inhibits lymphocyte proliferation; for treatment of RA
Leflunomide
It inhibits DNA synthesis in all cells by blocking dihydrofolate reductase
Methotrexate
Drug used to reverse the action of methotrexate
Leucovorin
An alkalyting agent used to treat leukemias and lymphomas prior to bone marrow transplantation
Busulfan
It is a commonly used analgesic, antipyretic and anti-inflammatory drug that directly stimulates the respiratory system and an inhibitor of the kreb’s cycle. It also has an anticoagulant property (antiplatelet activity) by inhibiting the action of cyclooxygenase
Salicylates
It decreases thromboxane and prostaglandin formation through inhibition of cyclooxygenase
Salicylates
Is a common cause of fatal drug poisoning in children characterized by…. xonrinue okes
Acute aspirin intoxication
An inhibitor of prostaglandin metabolism. It is commonly used as analgesic and antipyretic drug
Acetaminophen
Overdosage of this drug leads to hepatoxicity
Acetaminophen
toxic effects: mixed acid-base disturbance (metabolic acidoses and respiratory alkalosis), hypoglycemia, and Reye’s syndrome
Salicylates
Toxic effect: xyanosis due to methemoglobinemia, CNS depression and seizure
Acetaminophen
It has analgesic and anti-inflammatory actions with a lower risk of toxicities than salicylates and acetaminophen
Ibuprofen
Toxic effects: nausea, vomiting, blurred vision, abdominal pain, edema
Ibuprofen
Used in the treatment of acute schizonphrenia
Antipsychotic major tranquilizers
Specimen of choice for TDM
Serum or plasma
Whole blood EDTA sample is required for which drugs?
Cyclosporine and tacrolimus
When are trough concentrations drawn?
Immediately (or 30 minutes) before the next dose
Relationship between trough level and drug clearance rate
Inversely proportional
When are peak concentration drawn for orally administered drugs?
One hour after an orally administered dose (except digoxin)
When are peak concentrations drawn for IV infused drugs?
Peak levels are determined after the infusion is completed
How are drugs identified when using immunoassay method?
The drug must bind to antibody before it is identified
Method in which drugs are identified according to how far they have travelled or separated and to how they appear with each of the satains
Thin layer chromatography
Acidic drugs are extracted at what pH?
4.5
Alkaline drugs are extracted at what pH?
9.0
Method ideal for the separation of tricyclic antidepressants and its metabolites
HPLC
Gold standard for TDM
GC-MS
True or false
Toxicity is avoided as long as the dose of drug is within accepted therapeutic range
FALSE
Altered pharmacokinetics may result in toxicity even when the dose of drug is whin accepted therapeutic range. This is caused by the presence of unmeasured metabolites that are physiologically active and the presence of a higher than expected concentration of free drug
