main purpose of therapeutic drug monitoring

dosage that provides therapeutic effect based on stats from healthy people

two smaller purposes of therapeutic drug monitoring

4 factors that affect oral drugs

quantitative study of drug disposition in the body-mathematical relationships used to predict dosage adjustments

study of the biochemical and physiological effects of drugs and their mechanism of action

relationship between desired clinical effect and concentration in the plasma

time required for the serum concentration of a drug to decline by 50%

drug input and output are equal

usual timing to reach steady state

highest concentration reached after dosage

lowest concentration reached after dosage

dependent on drug's dissociation from dosing form, solubility in GI fluids, and diffusion across GI membranes into blood stream

fraction of drug absorbed into systemic circulation calculated by comparing IV and oral doses; depends on size, solubility, and ionization

concentration on one side of the membrane if higher than the other; 95% of all drug absorption

drug binds to carrier molecules and uses energy to go into blood stream

same as active, but follows concentration gradient

free vs bound (to albumin); active when free-able to cross cellular membranes and interact with receptors

drugs that primarily bind to albumin

drugs that primarily bind to globulins

condition that causes increased levels of free drugs due to binding sites being taken up by hemoglobin

breakdown of drugs into polar metabolites; substances absorbed from the intestine enter the hepatic portal system before entering general circulation; important in efficacy since it is how the drug is generated into the active metabolite

process occurring within the liver-hepatic uptake and metabolism during passage

biochemical pathway responsible for a large portion of drug metabolism

chemical structure of drug is modified through oxidation, reduction, or hydrolysis in the liver

intermediate is conjugated in the liver-soluble compound is formed

four factors affecting drug metabolism and biotransformation

drugs removed through hepatic metabolism, renal filtration, or combination of both

major elimination route; glomerular filtration, tubular secretion and reabsorption

an effective monitor of drug clearance; gent, tobra, amikacin, dig, vanc, and cyclosporine

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single most important factor in steady state levels

patients benefitting from therapeutic and desired effects of drug

patients not benefitting from the therapeutic and desired effects of drug

attributed to interindividual variation in genetic polymorphisms of drug metabolism pathways

gene group family that affects drug metabolism, family of enzymes within MFO system

glycosides and antiarrhythmics

cardiac glycoside used to treat CHF by inhibiting membrane Na-K-ATPase; absorbed by GI motility, eliminated by renal filtration; half life 38 hours; immunoassay

cardiac arrhythmia treatment; GI absorbed, hepatic metabolized; half-life 6-8 hours; immunoassay

cardiac arrhythmia treatment; GI absorption; renal and hepatic elimination; 4 hour half-life; immunoassay

cardiac arrhythmia treatment; GI absorption, hepatic metabolism elimination; half life 7 hours; immunoassay

treat gram-negative bacterial infections that are resistant to other less-toxic antibiotics; gent, tobra, amikacin, and kanamycin; most serious effects are nephrotoxicity and ototoxicity; IV or IM only-not for outpatients

glycopeptide antibiotic effective against gram-positive cocci and bacilli infections; IV infusion; toxicities include red man syndrome, nephrotoxicity and ototoxicity

flushing of extremities; sign of vanco toxicity

slow-acting barbituate that effectively controls several types of seizures

inactive form of phenobarbital; rapidly absorbed in GI tract and converted to phenobarbital; preferred when steady-state kinetics need to be established quickly

commonly used treatment for seizure disorders; used as short-term prophylactic agent in brain injury to prevent loss of functional tissue

injectable proform of phenytoin that is rapidly metabolized (75 minutes) to form the parent drug

used as a monotherapy for treatment of petit mal and absence seizures

treatment for various seizure disorders; less frequently used due to toxic affects-rash, leukopenia, nausea, vertigo, febrile reactions

used to control petit mal seizures; toxicity: nausea, vomiting, anorexia, dizziness, and lethargy

treatment for severe epilepsy; oral administration-GI absorption; known for toxicity; primarily indicated in severe epilepsies such as Lennox-Gastaut syndrome (children) and refractory epilepsy (adults)

may be indicated as monotherapy or in conjunction with other antiepileptic drugs in patients suffering from complex partial seizures with or without generalized seizures

treat patients with partial and generalized seizures (4)

a pro-drug that is almost immediately metabolized to licarbazepine; indicated for monotherapy of partial seizures and secondarily generalized tonic-clonic seizures

used in treatment of partial seizures; Adverse central nervous system (CNS) side effects: confusion, difficulty in speaking clearly (stuttering), mild sedation, and a tingling sensation in the body’s extremities, or paresthesia, especially in the hands and fingers

psychoactive drug orally administered to treat manic depression

a class of drugs used to treat depression, insomnia, extreme apathy, and loss of libido

an atypical antipsychotic used to treat otherwise treatment-refractory schizophrenia

a thienobenzodiazepine derivative that effectively treats schizophrenia, acute manic episodes, and recurrence of bipolar disorders

primary clinical use is suppression of graft-vs-host rejection of heterotopic transplanted organs

immunosuppressive 100 times more potent than cyclosporine

an antifungal agent with immunosuppressive activity; FDA approved for patients receiving kidney transplants

a lymphocyte proliferation inhibitor; used most commonly as supplemental therapy with cyclosporine and tacrolimus in renal transplant patients

antineoplastic; one of few which TDM offers benefit to therapeutic regimen; inhibits DNA synthesis in all cell

reverses effects of methotrexate at certain point so normal cells can divide and replicate

bronchodilator used in treatment of respiratory disorders such as asthma and stable COPD for those that cannot use inhaler or with nocturnal symptoms; effects include insomnia, tachycardia, seizures, arrhythmias, cardiorespiratory arrest