Lecture 13B - Rectal and Parenteral Administration Flashcards
Advantages of suppositories?
good route to administer drug when vomiting
fast systemic response
When is use of suppositories indicated?
for drugs inactivated by GI fluids when given orally
for drugs inactivated by the liver after oral administration
Disadvantages of suppositories?
patient acceptability (cultural influence)
drug absorption is irregular and difficult to predict
Example of drugs used as suppositories?
metronidazole (anaerobic infections, C difficile)
What is parenteral administration?
administration by infection
What are the types of parenteral administration?
intramuscular and intravenous administrations
What is injected IV?
only solutions
What must all parenteral products be?
sterile
When is parenteral the preferred route?
when rapid absorption is essential (emergency, unconscious patients)
What are parenteral administrations generally?
sterile solutions or suspensions of drugs in water
What are injections?
sterile solutions, emulsions or suspensions i water or non-aqueous liquid
injected in less than 15 minutes
What are infusions?
aqueous solutions
large volumes 100ml-1000ml
injected in more than 15min
Example of an infusion?
benzylpenicillin sodium (endocarditis, meningitis)
What is a depot preparation?
dispersion of the drug in an oily vehicle to give slow release of the drug
IM injection deep into skeletal muscle
Formulation of depot preparation?
viscous formulation, large volume (5mL maximum) injected
need to be injected in large muscle to decrease pain in swelling
What do depot preparations give?
slow release of the antibiotic for weeks
Example of a depot preparation?
benzathine penicillin G
What is benzathine penicillin G used for?
for people who have had acute rheumatic fever (a potential outcome of step pharyngitis) and need prophylaxis against further step infections
Powder for suspensions?
disperson of the drug in the oily vehicle lecithen and suspension stabilisers (surfactant polysorbate and polymer polyvinylpyrrolidone (Povidone)
powder is redispersed in water for injection
Advantages of depot preparations?
long lasting effect - release of the drug for 2-4 weeks
limited number of injections
Disadvantages of depot preparation?
negative patient acceptability due to pain
How can the pain of depot preparations be reduced?
adding lidocaine to the antibiotic injection
inability to discontinue the medication for weeks in case of adverse effects of the antibiotic
