General information Flashcards
What are MFOS &where are they embedded ?
mixed function oxidase system involved in the biotransformation. Cytochrome P450 has about 50 iso-enzymes. Microsomal enzymes are embedded in the smooth endoplasmic reticulum in the liver.
How are polar molecules excreted ?
Polar molecules have poor membrane permeability, thus, generally excreted unchanged.
How are lipid-soluble molecules excreted ?
Lipid-soluble molecules on the other hand can easily reach the intracellular microsomal enzymes and are metabolized into more polar metabolites.
The toxic metabolite of Paracetamol ?
Paracetamol has a toxic metabolite : N-acetyl P-benzoquinone, hepatic necrosis
The toxic metabolite of Cyclophosphamide ?
Cyclophosphamide has a toxic metabolite : acrolein, cystic hemorragy
Cascade of reactions proper to Alcohol &what is Disulfiram ?
alcohol and disulfiram : alcohol is first transformed into acetaldehyde (by alcohol dehydrogenase, a hepatic enzyme) and then into acetate (by aldehyde dehydrogenase). Disulfiram inhibits aldehyde dehydrogenase increasing levels of acetaldehyde that causes extremely unlpeasant, but not harmful, effects. It is an aversion therapy for alcohol addicts.
Which other molecule has same effect of Disulfiram when associated with alcohol ?
Metronidazole
Define Tachyphylaxis ?
tachyphylaxis : acute tolerance developing rapidly due to administration of a drug (indirectly-acting sympathomimetics) repeatedly in short intervals.
Two types of synergism ?
two types of synergism; summation and potentiation.
Three types of antagonism ?
three types of antagonism : chemical, physiological and pharmacological (competitive &non-competitive)
Antidote of Opioids ?
Antidote of Acetylcholine ?
naloxone and opioids,
acetylcholine and atropine.
