L53- Drug distribution Flashcards
1
Q
what 4 factors affect solubility?
A
- degree of ionisation
- molecular size
- interactions of functional group with the solvent
- crystal properties
2
Q
acidic drugs are ….in acidic conditions
A
less soluble
3
Q
what is partition coefficient?
A
the ratio of equilibrium concentration in oil and water
4
Q
what is the equation for partition coefficient?
A
Po/w= C(oil) /C(water)
5
Q
what number should the partition coefficient be to pass the GI tract?
A
high
6
Q
what type of molecules are favoured in the partition coefficient?
A
lipophilic molecules
7
Q
what are most drugs and why?
A
weak bases so they can ionise in the stomach, but will be less ionised in the intestine which is good
