Phosphodiesterase III inhibitors (pentoxifylline and cilostazol) are used to treat intermittent claudication.
Iron salts, such as ferrous sulfate, are used as iron supplements to treat iron deficiency anemia.
Memantine is a noncompetitive antagonist at the NMDA subtype of glutamate receptor.
Tolerance is a physiological state characterized by a reduced drug effect with repeated use of the drug. Higher doses are needed to produce the same effect.
Cross-tolerance means that individuals tolerant to one drug will be tolerant to other drugs in the same class, but not to drugs in other classes.
Dependence is characterized by signs and symptoms of withdrawal when drug levels fall.
Cross-tolerance and cross-dependence occur between all of the CNS sedatives, includ- ing the barbiturates, benzodiazepines, and ethanol.
Any other drug that is metabolized by the P-450 system will be altered by the presence of barbiturates.
Barbiturates both enhance GABA responses and mimic GABA by opening the chloride channel in the absence of GABA. The net result of both actions is an increase in inhibition in the CNS.
Benzodiazepines bind to a specific site associated with the GABAA receptor, which results in increased inhibition.
Most benzodiazepines are metabolized in the liver to active metabolites. In general the metabolites have slower elimination rates than the parent compound.
MCQ No. 1971 | IMA
For UV visible spectrum electronic excitation occur in the range of
For UV visible spectrum electronic excitation occur in the range of
Anonymous Quiz
40%
200-800 mμ
43%
400-800 mμ
12%
400-700 mμ
4%
300-600 mμ
MCQ No. 1972 | IMA
Which detector is used to detect cations & anions?
Which detector is used to detect cations & anions?
Anonymous Quiz
15%
Flourometric detector
55%
Conductivity detector
25%
Amperometric detector
5%
Refractive index detector
Definitions and Concepts Central to Understanding Pharmacokinetics
• Bioactivation
Either (1) conversion of prodrug to any active drug, or (2) conversion of the active drug to a reactive, electrophilic meta- bolic intermediate.
• Bioequivalence
Generally referring to overall ‘equal’ bioavailability between two comparable drugs; usually between generic and trade name formulations of a drug.
• Biotransformation
In general, the metabolic change of a lipophilic drug to a more hydrophilic metabolite allowing renal or biliary excretion.
• Blood–brain barrier
Protective mechanism for brain neurons; due to tight junctions (and lack of intercellular pores) in brain capillaries; highly lipophilic drugs may ‘overcome’ this barrier.
• Detoxification
The metabolic conversion of a reactive, electrophilic intermediate to a more stable, usually more hydrophilic compound.
• Enteral
GI administration of a drug.
• Enterohepatic recirculation
Sequence of initial GI absorption of drug followed by hepatic excretion into bile and small bowel, followed by subsequent GI reabsorption.
• Bioactivation
Either (1) conversion of prodrug to any active drug, or (2) conversion of the active drug to a reactive, electrophilic meta- bolic intermediate.
• Bioequivalence
Generally referring to overall ‘equal’ bioavailability between two comparable drugs; usually between generic and trade name formulations of a drug.
• Biotransformation
In general, the metabolic change of a lipophilic drug to a more hydrophilic metabolite allowing renal or biliary excretion.
• Blood–brain barrier
Protective mechanism for brain neurons; due to tight junctions (and lack of intercellular pores) in brain capillaries; highly lipophilic drugs may ‘overcome’ this barrier.
• Detoxification
The metabolic conversion of a reactive, electrophilic intermediate to a more stable, usually more hydrophilic compound.
• Enteral
GI administration of a drug.
• Enterohepatic recirculation
Sequence of initial GI absorption of drug followed by hepatic excretion into bile and small bowel, followed by subsequent GI reabsorption.
• First-pass effect
Drugs which have significant metabolism in the liver, before widespread systemic distribution—occurs after GI absorption, by way of portal vein to liver.
Drugs which have significant metabolism in the liver, before widespread systemic distribution—occurs after GI absorption, by way of portal vein to liver.
• Half-life
Duration of time for 50% of the absorbed and bioavailable drug to be metabolized and excreted.
Duration of time for 50% of the absorbed and bioavailable drug to be metabolized and excreted.
• Prodrug
A pharmacologically inactive precursor of the biologically active ‘drug’.
A pharmacologically inactive precursor of the biologically active ‘drug’.