Flashcards in Drug Absorption #2 Deck (94)
____ volume of liquid results in more RAPID emptying
increased; liquids in general empty very fast. they can empty even when there is food in the stomach (takes about 12-15 minutes)
_____ contents empty FASTER than _____ liquids
T/F There are receptors in the duodenum that detect increases in the osmotic pressure that use feedback mechanism
_____ increases osmotic pressure
_______: increases gastric emptying
_______: decreases gastric emptying
stress, anxiety- decrease
________: have no effect or slight increase in gastric emptying
_________: decrease gastric empyting
moderate intensity; vigorous
If you are on your ____ side: increase gastric emptying
If you are on your _____ side: decrease gastric emptying
T/F Gastric emptying is FASTER in older people
T/F Females have slower gastric emptying then males
What disease states INCREASE gastric emptying? (3)
-cholecystitis (inflammation of the gallbladder)
Gastritis, GERD, Gastric Carcinoma, Pyloric stenosis, Gastric Ulcers, Diabetic Gastroparesis, Hypothyroidism, Migraine, Pregnancy_______ gastric emptying
What drugs DECREASE gastric emptying? (4)
-isoniazid--> used to treat TB
What drugs INCREASE gastric emptying? (2)
T/F Food has a great impact on gastric emptying
TRUE: general you would want a patient to take solid dosage form on an empty stomach with a full glass of water
Why do we want to get the drug out of the stomach ASAP?
because it is not being absorbed in the stomach and it needs to get in the intestine
What is considered an empty stomach with food?
-30 minutes before a meal
-2 hours after a meal
Why do some drugs need to be taken with food? (2)
-if drug is irritating
-food increase absorption of some drugs
T/F You CAN NOT decrease saturation if given with food
FALSE: you can
How could food affect absorption of a drug? (3)
-change in pH
-interact with drug
Food ____ gastric emptying
Food changing the pH could do what?
When the drug Nitrofurantoin was given with food, more excretion (unchanged drug) occurred. Why?
When you give with food emptying is SLOWED making the drug stay in the stomach longer which allows more of the drug to dissolve in the stomach before it is emptied into the intestine
T/F Blood flow is static.
FALSE: there is first blood flow through the membrane then the drug is being carried away by the blood
rate limiting step
slowest step in the overall process that controls how fast the process will proceed
perfusion rate limited (2)
-blood flow step is the slowest step (#2)
-drug freely passes through the membrane with little resistance
ex. water and ethanol
diffusion or permeability rate limited
-difficult to cross the membrane, slowly crosses the membrane
ex.ribitol (large polar molecule)
When a drug is administered through the muscle (IM), then it only has to cross.....
the blood capillaries
Capillary walls are very ______ compared to the GI tract. What type of rate limited is this?
-molecules with HIGH molar weights easily cross the capillary wall
-perfusion rate limited
Would you expect gentamicin, a large polar water soluble molecule to be absorbed well?
NO, because it is big and its polar but if administered into muscle tissue it is readily absorbed