Pharm: Sedatives + Hypnotics Flashcards
What are the indications for phenobarbital?
Pre-operative sedation
What is the receptor for barbiturates?
GABA receptor agonist - opens a chloride channel
What is the indication for secobarbital?
Short term treatment of Insomnia
Used in acute psychosis
How do benzodiazepines function?
Bind to a site on GABA-a receptors that is separate from GABA. The function is to allow more chloride ions flow in once GABA binds for increased efficacy.
What are symptoms of benzodiazepine withdrawal and how is this prevented?
Restlessness, anxiety, weakness, generalized seizures
To avoid withdrawal:
- Taper 25% / week down to 50% of the dose
- Then once you’ve reached 50% of the original dose, drop to 1/8 the dose every 4-7 days
What kind of drugs are zolpidem and zaleplon? On what kind of receptor type do they act?
They are Z-hypnotics that act on the GABA-a type 1 receptors which are rapid onset for hypnosis or sleep.
Describe the MOA for propofol.
Acts on presynaptic cells to stimulate GABA release.
What population is etomidate a useful drug?
Good for patients with limited cardiovascular reserve.
It doesn’t lower blood pressure and is not analgesic.
What is important to remember when switching between a BZ and buspirone?
Buspirone is not cross tolerant with benzodiazepines, which means that it cannot replace a BZ and prevent withdrawal symptoms of BZs. It acts on serotonin 1A receptors NOT GABA receptors.
What are two advantages of using ramelteon as a hypnotic agent?
Melatonin receptor agonist.
Shortens latency to sleep with no rebound insomnia
No withdrawal symptoms.
What are the recommended guidelines for BZ use in patients with insomnia that do not respond to hypnotics?
- The hypnotic should be used for short term use
- for its specific indications
- the cheapest one should be prescribed
- no switching between similar class hypnotics unless there is an allergy to a specific one
- patients that do not respond to these should NOT be prescribed another one
What are indications for alprazolam?
Panic disorders
What are indications for meprobamate?
Short-term anxiety and sedative hypnotic
Describe the efficacy of oral midazolam as a premedicant to sedate and calm peds patients.
Given orally in peds patients. 90% achieved satisfactory sedation and axiolysis and ease of separation from parents or guardians within 30 minutes of administration.
What are advantages and disadvantages to using buspirone in stead of BZ?
Adv.
- relief of anxiety within 2-4 weeks
- no addiction, abuse, or withdrawal
- used with alcohol or other CNS agents
- modulates 5HT at certain receptors
Dis.
- less effective than BZ
- not effective in panic disorders