Foundations: Meds
Give the right drug to the right patient in the right dose by the right
route at the right time.
Chemical: Describes the molecular structure. EX: Acetylsalicylic acid
Generic: Name given by the manufacturer. Ex: aspirin
Trade/Brand: Name the manufacturer markets the drug. EX: Bayer (always
has a trade mark)
Pharmacokinetics: Movement of drugs through the body.
Medicine goes in your body via mouth or whatever route, absorption is how
it gets in which is through the blood stream. The distribution is where it
goes to, if you have a headache, you want it to go to your head. So this is
where the drug leaves the blood to the interstitial spaces of tissues into the
cells. Metabolism is how the drug is broken down. Excretion is how the
med leaves the body. (Poop/pee)
There’s different rates of absorption based on what route the medication is
absorbed. EX: IV, PO. If the full amount is absorbed, you will see a more
Intense effect.
Enteral (GI Tract)
Parenteral (outside GI tract)
What can affect the absorption
Rate of dissolution. The quicker it dissolves the faster it is absorbed.
Surface Area: In the small intestine there’s microvilli, there’s a large
surface area. Larger surface area> better absorption
If there’s high blood flow at a site there’s more absorption. Higher
blood flow higher absorption rate, lower blood flow lower absorption
rate.
Fast absorption with lipid solubility
PH diff between plasma and site of administration help with ionization
so they increase absorption where there’s a diff between PH.
Absorption- IV
Advantages
There are no barriers with IV bc it goes directly into the blood stream.
The absorption pattern is complete. Its Instantaneous and goes directly
in blood stream.
It’s rapid onset, follow up 15-30 mins after distributing med.
We don’t always need to give meds via IV
, IV is a great way to give large fluid volumes.
Irritant drugs can be diluted in IV
Disadvantages
You need to be specially trained to distribute IV which can be
inconvenient for pt.
It’s expensive
It’s irreversible. It goes directly in bloodstream and that could cause a
problem, so you need to observe pt very closely.
Pt can get embolism via IV insertion; a clot can happen and cause
embolism. Certain hypertonic fluids could destroy red blood cells. If IV
fluid isn’t fully dissolved it can cause embolus.
Davis Drug Guide: Vancomycin is poorly absorbed so its given via IV. It is
irritating to tissues and causes necrosis and severe pain with extravasation.
Absorption: SUB Q IM
Minimal to no barriers with Intramuscular SQ sub cut.
Could be absorbed rapidly or slowly, depends on what we want the
drug to do.
Advantages
Can administer drugs what don’t dissolve completely, (poorly soluble). BC it’s
going in the muscle it’s okay if its not completely dissolved.
You can administer drugs (DEPOT) to be absorbed over a long period of time.
Disadvantages
It hurts, painful with each does
It’s inconvenient, need the equipment
Not good for pt on anticoagulant therapy
There is a volume limit !!!! 1ml for deltoid, 1ml for ALL subq sites 3ML
for other IM sites
PO- BY MOUTH!!!
There’s 2 layers of barriers. The main barrier is the epithelial cells along the
GI tract, med has to pass through the cells and it’s a little difficult for them to
go through them
Absorption Pattern
Highly variable. The absorption rate depends on so many different
factors for ex:
Solubility & Stability of the drug
Gastric emptying time
Food if gut- if you have other food in the stomach
It pt is taking other drugs
The PH of gastric intestine
Give the right drug to the right patient in the right dose by the right
route at the right time.
Chemical: Describes the molecular structure. EX: Acetylsalicylic acid
Generic: Name given by the manufacturer. Ex: aspirin
Trade/Brand: Name the manufacturer markets the drug. EX: Bayer (always
has a trade mark)
Pharmacokinetics: Movement of drugs through the body.
Medicine goes in your body via mouth or whatever route, absorption is how
it gets in which is through the blood stream. The distribution is where it
goes to, if you have a headache, you want it to go to your head. So this is
where the drug leaves the blood to the interstitial spaces of tissues into the
cells. Metabolism is how the drug is broken down. Excretion is how the
med leaves the body. (Poop/pee)
There’s different rates of absorption based on what route the medication is
absorbed. EX: IV, PO. If the full amount is absorbed, you will see a more
Intense effect.
Enteral (GI Tract)
Parenteral (outside GI tract)
What can affect the absorption
Rate of dissolution. The quicker it dissolves the faster it is absorbed.
Surface Area: In the small intestine there’s microvilli, there’s a large
surface area. Larger surface area> better absorption
If there’s high blood flow at a site there’s more absorption. Higher
blood flow higher absorption rate, lower blood flow lower absorption
rate.
Fast absorption with lipid solubility
PH diff between plasma and site of administration help with ionization
so they increase absorption where there’s a diff between PH.
Absorption- IV
Advantages
There are no barriers with IV bc it goes directly into the blood stream.
The absorption pattern is complete. Its Instantaneous and goes directly
in blood stream.
It’s rapid onset, follow up 15-30 mins after distributing med.
We don’t always need to give meds via IV
, IV is a great way to give large fluid volumes.
Irritant drugs can be diluted in IV
Disadvantages
You need to be specially trained to distribute IV which can be
inconvenient for pt.
It’s expensive
It’s irreversible. It goes directly in bloodstream and that could cause a
problem, so you need to observe pt very closely.
Pt can get embolism via IV insertion; a clot can happen and cause
embolism. Certain hypertonic fluids could destroy red blood cells. If IV
fluid isn’t fully dissolved it can cause embolus.
Davis Drug Guide: Vancomycin is poorly absorbed so its given via IV. It is
irritating to tissues and causes necrosis and severe pain with extravasation.
Absorption: SUB Q IM
Minimal to no barriers with Intramuscular SQ sub cut.
Could be absorbed rapidly or slowly, depends on what we want the
drug to do.
Advantages
Can administer drugs what don’t dissolve completely, (poorly soluble). BC it’s
going in the muscle it’s okay if its not completely dissolved.
You can administer drugs (DEPOT) to be absorbed over a long period of time.
Disadvantages
It hurts, painful with each does
It’s inconvenient, need the equipment
Not good for pt on anticoagulant therapy
There is a volume limit !!!! 1ml for deltoid, 1ml for ALL subq sites 3ML
for other IM sites
PO- BY MOUTH!!!
There’s 2 layers of barriers. The main barrier is the epithelial cells along the
GI tract, med has to pass through the cells and it’s a little difficult for them to
go through them
Absorption Pattern
Highly variable. The absorption rate depends on so many different
factors for ex:
Solubility & Stability of the drug
Gastric emptying time
Food if gut- if you have other food in the stomach
It pt is taking other drugs
The PH of gastric intestine
