Pharmaceutical Technology 2 Flashcards
(51 cards)
Types of injections
- Intramuscular - into muscle
- Subcutaneous - into subcutaneous layer
- Intravenous - into vein
- Intradermal - into epidermis
- Intrathecal - into spinal cord
(Intrathecal injections) Drug delivered into ______ flows directly to the ____.
CSF
Brain
How can drugs be administered for intrathecal injections?
a. Into reservoir (Ommaya)
b. Via lower back
CSF is a clear solution made up of?
99% water
1% protein, ions, neurotransmitters & glucose
pH of CSF
~7.3
Volume of CSF
150mL, 430-530mL produced per day
CSF has variable ____, ____ and ___.
Viscosity
Flow rate
Pressure
Can intrathecal cross the BBB?
Yes
Advantages of parenteral delivery 1
Bypasses hepatic 1st pass metabolism
Advantages of parenteral delivery 2
Can control dosage
- Relatively low drug concentration and low toxicity
Advantages of parenteral delivery 3
Direct access to brain (intrathecal)
Advantages of parenteral delivery 4
Sustained release (intramuscular depot, intrathecal reservoirs)
Advantages of parenteral delivery 5
Ideal for non-compliant, unconscious or dysphagic patients
From blood to brain, drug solution flows through ______.
Circulatory system
- Reticuloendothelial system (RES)
- Unless there is active targeting, drug will distribute everywhere
Drugs must bypass ____ to access the brain.
BBB
The blood brain barrier blocks uptake of __% of small molecular drug candidates.
98%
Types of transportation across BBB
Paracellular (tight junctions)
Transcellular
Examples of active efflux transporters
P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), multi-drug resistance proteins (MRP)
What are active efflux transporters?
Removes drugs from organ (brain) into the lumen (blood)
Types of transporters in BBB
- Active efflux
- Carrier mediated (CMT)
- Receptor-mediated (RMT)
Modified Lipinski’s for CNS - MW
<450 Da
Modified Lipinski’s for CNS - hydrogen bond donors
<3
Modified Lipinski’s for CNS - hydrogen bond acceptors
<7
Modified Lipinski’s for CNS m- LogP
1-3
