Pharmaceutics quiz 2 Flashcards
How non-oral dosage forms differ from oral dosage forms
tend to be liquids, solubilized in aqueous solvents
5 important considerations for pharmaceutical liquids
Tonicity- 0.9% NaCl sterility- steam, heat, UV etc preservatives- parabens, benzyl compounds particulate matter- contaminants solution pH - buffers
tonicity
RBC have the same tone as blood, isotonic plasma, RBC and 0.9 NaCl is the same
same number of solute to body fluids
hypotonic solution
0.45% NaCl - give to patient that is hyperglycemia
hypertonic solution
3-5% NaCl- given to patients that have diarrhea or vomiting
how to calculate isotonicity
- cryoscopy
- NaCl equivalent
a. find amount g in ml solution
b. g amount in NaCl x E value
how much NaCl in solution
subtract steps 3 and 2
sterility
destroys or eliminates all forms of microbial life and carried in healthcare facilities by physical or chemical methods - used to remove contaminants by purifying the system
steam
moist heat, most common
MOA: causes bacteria/spores/cellular proteins to coagulate and die
autoclave: 127 degrees and 15-30 mins
pressure used to get the temperature higher, temp is what kills the bacteria
NOT: thermolabile drugs, moisture sensitive drugs/oils/fats/powders
FOR: aqueous solutions, glassware/containers
dry heat
simplest heat, longer than steam 180 for 45 mins dehydrates and breaks down the cell membranes NOT: heat sensative FOR: glass/metal
ionizing radiation
method for materials that can’t withstand heat
surfaces only: low penetration capacity - ionizes and damages cell membrane structure
Gas
only one: ethylene oxide MOA: alkylates DNA and RNA of microorganisms conditions: 450-1200 mg/L temp: 37-63 degrees time: 1-6 hours cycle more than 14 hours humidity: 40-60% FOR: surgical instruments/gloves/plastic syringes
Filturation
doesn't kill - remove microorganisms filter size depends on how to remove the smallest visible particle FOR: media can't be autoclaved careful with filter HEPA > 0.3 microm membrane filtration > 0.22 microm
preservatives
protect from contaminants bacteriostatic: keep it from growing must label with specific concentration not in container with more than 30 mL multi-dose containers not used in neonates (benzyl alcohol toxicity), spinal injections like epidurals ex: benzyl alcohol, parabens WFI: water for injection
particulate matter
non-oral DF: free from foreign particles
ex: glass, water, glass in one vial
clarity and sterility can occur in the same step
solution pH
physiologic pH 7-7.4 depends on ROA uses buffers to maintain pH pH > 9 - kills cells (necrosis) pH < 3 Burns! bet range 6.8-7.4
parenteral
par- outside
enteral- intestine
IV, IM, SubQ
sterile, pyrogen-free
Pros of parenteral
faster onset of action bioavailability high - not many enzymes to break down depot: prodrug IM - once /3 months 1st pass metabolism avoided continuous drug delivery - IV infusion accuracy / predictibility
IV- where, why, when, how much
how: superficial vein
why: rapid onset of action (30-60 secs)
used: needle/ IV catheter tubing
when: quick action
how much: small or large
volumes for adult: 25-30 ml/kg/day
IV pros/cons
pros: rapid onset of action, admin large amounts, useful for irritating or hypertonic solutions, provides high systemic bioavailability
cons: injection leaks from vein and harms healthy nearby tissues, speed of drug admin should be constant, reversal of drug action not possible, oily solutions preferred
why is insulin given subq
insulin can’t be taken orally because the acidic environment of the stomach destroys the insulin - needs to be injected, needs to be released slowly in the blood stream so a fast drop won’t lead to hypoglycemia. patients can inject it themself
small parenteral vs large parenterals
SVP- unit dose/multiple dose, total volume < 100 mL
LVP- >100ml, IV infusions, no preservatives ex: TPNs
how and why haldoldeconate differs from haloperidol (onset and duration)
haldoperidol- immediate release IM, water soluble, aqueous vehicle, 10-20 min activity
haldol- haldoperidol with a long fatty acid chain (prodrug) 3-4 weeks 1-2mL, oil base makes it release slow, Depot injection, does not have to be refridgerated
why intradermal route is good for immune testing. why do we admin tb intradermally
makes injection safer. do not need trained staff, local effects, antigen prosenting cells, many capillaries along with many immune cells in the dermis
explain USP nomenclature for injectable dosage forms
“injection”: aqueous/oil - already mixed IV, IM, SC
“_____ for injection”: dry powder to reconstitute, not suitable in solvent. freeze dried. IM, SQ, IV
“___ for injectable suspension”: pre-made, no reconstitute, IM, SC, intra-articular NOT IV bc it has particles, can be a vaccine!
“emulsion”: drug-water insoluble, shake well before use, get up faster with a smaller amount of sedation. <1 microm, soy bean oil, comes into a onainer already has a vehicle, given IV
understand how vehicles (aqueous/non-aqueous) are chosen for parenteral admin
Aqueous:
- sterile water for injection USP: sterilized and packaged into a single dose of NMT 1 L volume
- bacteriostatic WFI: packaged into vials with one or more antimicrobial agent <30 mL dose
- NaCl injection: 0.9% isotonic, for sterile isotonic solutions with no preservatives
- Bacteriostatic NaCl injection USP: 1 or more antimicrobial agent
Non-aqueous vehicles:
- inert, non-irritating, non-toxic
- miscible with body fluid
- when- drug insoluble - depot effect
- fixed oils - soybean, sesame, glycerin, polyethylene glycol
understand precautions while storing and handling parenteral drugs
Do not freeze!
describe why modified injectable systems are useful
in vitro/ in vivo stabilization
improved bioavailability
enhanced patient compliance
reduced dosing frequency
understand how a liposome is made and the mechanism of drug release with doxil and amphotericin B
liposome is made of phospholipids - drug can be in a liposome or in the liposome wall - hydrophilic head and hydrophobic tail
explain how polymeric microparticles are useful for parenteral delivery with respect to lupron depot and neulasta
made using polymers to extend DOA, up to 3 months, IV or subQ, biodegradable polymers- erosion of the matrix will release the drug
usually cant be given IV because of particles
IM- pros/cons - size of needle
pros: useful for suspensions/irritating solutions, large muscle mass available, slow and uniform absorption
cons: skilled person needed for drug admin, careless admin may result in damage to nerves
1 1/2 inch needle, 90 degrees
10-20 min onset
can be immediate or depot release
understand how lung structure and morphology will influence how a drug will be absorbed
- lungs have a large surface area for absorption
- administered by the nasal or respiratory route for systemic or local effect
- SA for drug delivery - for drug delivery
- adult human has alveoli
- alveolar - less mucus
- goblet cells keep epithelial from drying out
- pulmonary cells reduce surface tension and prevent collapse of the air/gas interface
deep lung- 17023 respiratory bronchioles aveoli
upper lung 1-16 ends with terminal bronchiol
explain how survanta (beractant) helps premature infants
bovine extracted from bovine lungs for premature infants, mimics surfactants to reduce thickness of mucus in deep lungs and prevent collapse of alveoli and reduce surface tension at air/gas interface , not for injection
understand the benefit of conducting and respiratory zone in the lungs
conducting zone- 1-16, trachea and branching bronchioles, ends with terminal bronchiole, moves air into and out of lungs during each breath, warms air to 37 degrees
respiratory zone- branches 16-23, all structures that partake in gas exchange, begins with respiratory bronchioles, sub-divide into alveolar sacs and alveoli,
MDI
Metered dose inhalers have a faster onset of action. locally acting and less side-effects.
conventional liposomes
normal, made of neg and positive lipids
PEGylated liposome
lipids covered in polyethylene glycol - hides the liposome from white blood cells so they can stay in blood longer
ligand-targeted liposome
formed and various things are added onto it
just the something or PEG and something
theranostic liposome
therapeutic + diagnostic
functionalized imaging agent added to the phospholipid head and then something is added for finding tumors in the body!
subcutaneous - needle length, location, drug, pro cons, examples
1/2 - 1 inch needle 45 degree angle in the fatty layer of the dermis, drug travels through adipose tissue to the blood stream
absorption of the drug is slow and complete
pros: self admin and slow and complete absorption
cons: considered to be painful irritant drugs and cause tissue damage
adipose tissue more permeable than epithelial tissue
AMBisome
amphotericin B for injection - lower toxicity profile - IV infusion over 2 hours - lipophilic in bilayer- phospholipids make liposomes - cholesterol - not given in bolus dose!! for anti-fungal use
Doxil
Doxorubicin HCl - hydrophilic, lives inside the liposome, PEG makes it circulate for longer periods of time, longer half-life, given as an IV infusion, tumor tissues have more spaces in the cells so it is made concentrated in tumor areas, given as infusion not as bolus dose because can get into extraneous fluids at a higher surface area and can cause a site reaction - damage to surrounding tissues!
neulasta
neupogen (11 days)- no PEG - 1 cycle with PEG, replenishes neutrophils (WBC) when have cancer size 200 nm - replaces chemo patients RBC, polymeric micro-particle
lupron
depot, suspension, long-acting, pre-filled syringe availability, drug and powder and chamber that separates it so you can mix the two together-
