Pharmacogenetics Flashcards
Describe how genomics can have an effect on drug metabolism and pharmacokinetics.
If the patient has a gene mutation where they do not adequately make certain metabolic enzymes, the drug can stay around longer and have a greater risk of reaching toxic levels
What is slow acetylation and who is the most effected?
Phase II metabolic enzyme N-acetyltransferase is inefficient. Most seen in Egyptian population
______ are enzymes in the liver involved in the oxidation of many drugs and environmental agents.
Cytochrome P450 (CYP) enzymes
CYP2D6 metabolizes about 25% of all drugs. What is its role in metabolism?
Removes methyl groups from oxygen
What are the classic signs of too much of a cholinergic agonist?
Nausea, vomiting, excessive sweating, headache, runny nose, hot flashes
You prescribe a patient with cevimeline as a muscarinic agonist to treat dry mouth. The patient calls you with multiple adverse side effects? What pharmacogenetic problem could be the cause?
Allelic variations in CYP2D6 causing inefficient metabolism
Why might a patient have poorer outcomes when treated for breast cancer with tamoxifen?
Tamoxifen must be oxidized by CYP2D6 to work. If there is allelic mutations in the enzyme it may not work
What can be the adverse reactions to codeine?
CYP2D6 poor metabolizers: codeine ineffective
CYP2D6 ultra metabolizers: severe abdominal pain
CYP2C9 poor metabolizers may have serious bleeding complications when taking ________.
Warfarin
*drug is making blood thinner than expected because it is not being metabolized
Succinylcholine is metabolized by plasma cholinesterase. What is the effect of taking this drug with inefficient plasma cholinesterase enzyme activity?
Prolonged apnea
Genetic mutations involving the Ryanodine Receptor is an example of genetics affecting ___________.
pharmacodynamics
Mutant alleles of the ryanodine receptor will cause what disorder?
Malignant hyperthermia often triggered by volatile anesthetics
*due to abnormal Ca++ release from SR
