Tube problems Flashcards
phenytoin
binds to the tube
carbemazepine
binds to the tube
diazepam
binds to the tube
solution for using drugs that bind to the tube
administer with higher volume of water (30-60mls)
hydrophobic drugs
bind to the tube
hydrophilic drugs
do not bind to the tube
drugs in acidic solutions
direct interaction with the drug and feed causing tube blockage
chlorphenamine
direct interaction with the drug and feed causing tube blockage
promethazine
direct interaction with the drug and feed causing tube blockage
solution for drugs that cause a direct interaction between the drug and feed causing tube blockage
use alternative routes if possible
avoid using syrups
dilute drug as much as possible
flush before and after administration
why do some drugs bind to the tube
hydrophobic drugs bind to the hydrophobic tube material
hydrophobic drugs bind to the tube
hydrophilic drugs do not bind to the tube
why do some drugs directly interact with the feed to cause a blockage?
drugs denature the proteins or fats in the feed
cause them to precipitate out
causes a blockage in the tube
fluroquinolones
direct interaction with drug and feed causing reduced drug absorption
ciprofloxacin
direct interaction with drug and feed causing reduced drug absorption (greatest loss in comparison to other fluoroquinolone)
ofloxacin
direct interaction with drug and feed causing reduced drug absorption (less loss than ciprofloxacin but not as little as moxifloxacin)
moxifloxacin
direct interaction with drug and feed causing reduced drug absorption (least loss out of all the fluoroquinolone)
why do some drugs and feed have an interaction that causes reduced drug absorption?
drug and feed itnteraction
drugs bind and complex with metal ions in the feed which causes reduced drug absorption
fluroquinolones bind with alkali metals and multivalent ions (for example Calcium ions (Ca) and Magnesium ions (Mg)
because they are bound and complexed with the metal ions the drug molecules aren’t free and therefore cannot be absorbed!!!
what should you do if using a drug that is known to bind with the feed and cause reduced absorption?
be aware of the feed routine
stop feed 2 hours before and re-start 2 hours after drug administration
flushing required
penicillin
drug requires administration on an empty stomach
ketoconazole
drug requires administration on an empty stomach
tetracyclines
drug required administration on an empty stomach
what should you do if you are using a drug that you know needs administered on an empty stomach
be aware of the feed routine
stop feed 2 hours before and re-start feed 2 hours after drug adminsitratiom
what kind of feeding would be inappropriate if you are using medicines that require administration on an empty stomach>
continuous
NJ route (as stomach is bypassed)
what kind of feeding would be appropriate if you are using medicines that required administration on an empty stomach?
bolus or intermittent
what BNF warning applies to drugs that require administration on an empty stomach
23
under medicinal forms –> cautionary and advisory labels
what problem can sorbital cause
large quantity of sorbitol (excipient) may cause osmotic diarrhoea
remember multiple medicines may have the same excipients- additive effect
what problem can liquids with high osmolarity cause and how can this be avoided
high osmolarity may cause osmotic diarrhoea
dilute liquid to reduce osmolarity
remember multiple medicines may have the same excipients- additive effect
hydrochoride salts
direct interaction of drug and feed causing blockages
malleates
direct interaction of drug and feed causing blockages
tartrates
direct interaction of drug and feed causing blockages
warfarin
direct interaction between feed and drug causing reduced drug absorption
phenytoin
direct interaction between feed and drug causing reduced drug absorption
