CNS depressants and Muscle Relaxants Flashcards
What are hypnotics and what is the relationship between hypnotics and sedatives?
Drugs that cause sleep.
A sedative can become a hypnotic if given in large enough doses
What are sedatives?
Drugs that reduce nervousness, excitability and irritability without causing sleep
What are the three main groups of sedatives-hypnotics?
Barbiturates
Benzodiazepines
Miscellaneous drugs/ Nonbenzodiazepines
What is REM interference?
A drug-induced reduction of REM sleep time
What is REM rebound?
Excessive REM sleep following discontinuation of a sleep altering drug
Name a long acting, intermediate acting and short acting benzodiazepine
L: Diazepam
I: Lorazepam
S: Midazolam HCL
What is the MOA of benzodiazepines and what are 2 favourable characteristics
Specifically affect the hypothalamic, limbic and thalamic systems of the brain
Do not suppress REM sleep as much as barbiturates and do not increase metabolism of other drugs
What are the drug effects of benzodiazepines?
Controls agitation and anxiety
Reduces excessive sensory stimulation, inducing sleep
Skeletal muscle relaxation
What are the indications of benzodiazepines?
Sedation
Sleep induction
Skeletal muscle relaxation
Agitation or anxiety relief
Anxiety-related depression
Treatment of acute seizure disorders
Treatment of alcohol withdrawal
Short-term therapy for insomnia
What are the adverse effects of benzodiazepines?
Headache
Drowsiness
Paradoxical excitement or nervousness
Dizziness
Vertigo
Lethargy
Fall hazard for older adults
Cognitive impairment
Hangover effect or daytime sleepiness
Amnesia (Sometimes used prophylactically)
What are the contraindications of benzodiazepines?
Glaucoma
Pregnancy
What are signs of a benzodiazepine OD?
Somnolence
Confusion
Coma
Diminished reflexes
What is the antidote for OD on a benzodiazepine?
Flumanezil
What are possible interactions of benzodiazepines?
Alcohol
Opioids
Grapefruit (Prolonged effect)
Kava and valerian
What is the first clinically available benzodiazepine drug?
Diazepam
When is midazolam most commonly used?
Preop and for procedural sedation
What is the onset of lorazepam and what is a consideration?
Induces sleep within 30 to 60 minutes
Longer onset of action so it is recommended to take it around 1 hour before going to bed
What is the max daily dosage of lorazepam?
4 mg
What is zopiclone?
A short-acting benzodiazepinelike drug
Indicated for short term treatment of insomnia and should be limited to 7-10 days of treatment
Contraindicated in people <18
What is Kava? (Indications, contraindications, interactions, adverse effects)
Relieves anxiety, stress and restlessness
AE: Yellow skin discolouration, scaly skin and visual disturbances
IE: Alcohol, barbiturates, psychoactive drugs
CI: Liver disease, alcoholism, parkinsons, alcoholism, those operating heavy machinery, breastfeeding and pregnant women
What is valerian? (Indications, contraindications, interactions, adverse effects)
ID: Anxiety, restlessness and sleep disorders
AE: CNS depression, hepatotoxicity, nausea, vomiting, anorexia, headache, restlessness, insomia
IE: CNS depressants, MAOIs, Phenytoin, warfarin, alcohol
CI: Cardiac and liver disease, heavy machinery use
Why aren’t barbiturates used as commonly today?
Safety and efficacy of benzodiazepines
Low therapeutic index (Easy to become toxic)
What is the MOA of barbiturates
Act primarily on the reticular formation (brain stem)
By potentiating the action of GABA, nerve impulses traveling in the cerebral cortex are inhibited
What are the indications of barbiturates?
Sedatives
Anticonvulsants
Anesthesia for surgeries
