Salts and solubility Flashcards
Why do drugs have salts?
to help stabilize acidic/basic functional groups
Therapeutic advantages of salts
oral bioavailability
dose formulations
routes of administrations
What are drug molecules classified as due to the fact they are carbon-based?
organic compounds
Do organic/inorganic salts contain drugs?
no
What are the 3 advantages of salts
- they rapidly dissociate
- allows for immediate solvation
- multiple possibilities for ion dipole interactions
What are common water soluble organic salts?
sugars
sugar analogs
glycolysis and CAC intermediates
Lipid soluble organic salts decrease water solubility of drugs. Why would this be good?
increased bioavailability
increased palatability of oral suspensions
increased duration
Should organic acids/bases be mixed in the same IV bag?
no, you’d get ppt
Can organic acids and bases be administered through different IV lines?
yes
A high P and log P indicate?
a more lipid soluble drug
Halogens and hydrocarbons enhance what kind of solubility?
lipid
What kind of soluble drug would you want in renal dysfunction ?
lipid
What kind of drug would you want for a patient with hepatic dysfunction?
a drug that is primarily eliminated by the kidney
What kind of solubility do you need to go from oral administration to dissolution in the GI tract?
water
What kind of solubility do you need to go from dissolution in the GI tract to penetration through the GI Mucosal Membrane?
lipid
prodrug
molecule that has been covalently modified to either an inactive/ weakly active analog in order to achieve a specific therapeutic benefit
bioactivation
after prodrug is administered it releases the original active drug molecule
What are some commonly used esters of carboxylic acids?
methyl
ethyl
propyl
isopropyl
t-butyl
What are some lipophilic groups that hydroxyl and phenol groups can be modified with?
acetate
tebutate
benzoate
propionate
cypionate
pivalate
valerate
What are some hydrophilic groups that hydroxyl and phenol groups can be modified with?
sodium phosphate ester
sodium succinate ester
Which has increased water solubility: Ampicillin or Amoxicillin? Why?
Amoxicillin, the OH group
Major purposes of drug metabolism
enhancing water solubility of drug molecules and enhancing elimination
detoxifying the drug
converting and inactive prodrug to its active analog
What kind of soluble compound does metabolism usually produce?
water
Which are more prone to metabolism: water or lipid soluble drugs?
lipid
Therapeutic advantages of enhancing water solubility
enhance solvation and dissolution in the GI tract
allows of preparation of concentrated IV, ophthalmic, and optic solutions
allows certain compounds to reach adequate concentrations in the urine
requires less metabolism and are less likely to have drug interactions with compounds that alter hepatic oxidative enzymes
Therapeutic advantages of enhancing lipid solubility
allows to pass through lipid belayers in GI Mucosal membrane
allows drug to cross blood brain barrier
allows for use of IM/ subcutaneous depot injections
greater plasma protein binding -> longer duration of action
increase palatability
delay dissolution
enhance absorption of oral, nasal inhalation, topical creams, or ointments
