CNS drugs Flashcards
CNS Stimulants
Amphetamine-like drugs
Analeptics
CNS Stimulants
amphetamine-like drugs:
methylphenidate
modafinil
armodafinil
Analeptics:
theophylline
Amphetamine-Like Drugs
methylphenidate
methylphenidate
ROUTE
AND SCHEDULE
PO,
transdermal patch,
schedule II
methylphenidate
MOA
increase dopamine & norepinephrine
Increase attention span & cognitive performance (memory, reading)
methylphenidate
INDICATION
ADHD,
narcolepsy
decrease impulsiveness, hyperactivity, and restlessness for ADHD
Amphetamine-Like Drugs
2
SCHEDULE IV
modafinil
armodafinil
modafinil
armodafinil- LESS RISK OF ABUSE
SCHEDULE
Schedule IV
modafinil
armodafinil- LESS RISK OF ABUSE
INDICATION
narcolepsy,
jet lag,
ADHD,
sleep apnea
Sleep apnea: periods of apnea when asleep requiring the patient to wake up and breath, either central (associated with CNS disorder) or obstructive (obesity)
Nursing
Amphetamines & Amphetamine-like drugs
methylphenidate
modafinil
armodafinil- LESS RISK OF ABUSE
Give early in the day (it’s a stimulant => insomnia)
Report irregular heartbeat, palpitation, HTN
Record height, weight, and growth of children (weight loss)
Avoid alcohol, caffeine, nicotine
Use sugarless gum to relieve dry mouth
Do not stop abruptly; taper off to avoid withdrawal symptoms
N/V, muscle weakness, HA, depression
Counseling must also be used
long term use causes dependence and abuse-disorder
Excreted in breast milk (avoid while breastfeeding)
May cause tics (report to provider)
Analeptics
theophylline
theophylline
MOA
stimulation of the brain stem
theophylline
INDICATION
(PO, IV)
IV:
neonatal apnea (stimulate respiration in newborns)
IV: Emergency respiratory depression
(caused by CNS depressant OD)
IV: Anesthetic recovery
IV/PO:
Bronchodilator
(for asthma, COPD, status asthmaticus)
theophylline
SIDE EFFECTS
restlessness, tremors, twitching, insomnia, seizure diuresis, tinnitus, tachycardia, palpitations, dysrhythmia dependence, withdrawal symptoms
CNS DEPRESSANTS
Effects of CNS depressants
Barbiturates (-barbital)
Benzodiazepines (-pam, -lam)
Nonbenzodiazepine hypnotics
zolpidem
Anesthesia
Types
Types of anesthetics
Inhalation (nitrous oxide, -flurane)
IV (etomidate, propofol, ketamine)
Other IV drugs used for anesthesia
Benzodiazepine
Opioid
Neuromuscular blockers
Succinylcholine
vecuronium
Regional anesthesia (-caine)
CNS Depressants Action
Sedation
Hypnosis
Anesthesia
Not all drugs are used to achieve all levels (sedative, hypnotic, & anaesthetic)
anterograde amnesia: difficulty recalling events that occur after dosing
DT: delirium tremens: shaking, confusion, and hallucinations (look up CIWA assessment tool)
CNS Depressants Action
Sedation
Indication:
anxiety,
muscle spasm,
ETOH withdrawal (DTs)
Effect:
Diminish physical & mental responses
No effect on consciousness (no hypnotic effect)
CNS Depressants Action
Hypnosis
Indication:
induction of anesthesia,
insomnia
Effect:
sleep,
anterograde amnesia
CNS Depressants Action
Anesthesia
maintenance of anesthesia
Effect: loss of consciousness, loss of reflexes - blink, - gag, - ANS
CNS Depressants Action
SIDE EFFECTS/ADVERSE REACTIONS
Overdose:
Resp. depression,
severe low BP,
DEATH
Not all drugs are used to achieve all levels (sedative, hypnotic, & anaesthetic)
Barbiturates
Schedule
Schedule II, III, IV
Barbiturates
MOA
GABA stimulation (an inhibitory neurotransmitter)
antiepileptic = anticonvulsant = anti-seizure
GABA: gamma-aminobutyric acid (an inhibitory neurotransmitter)
suicidal ideation, erectile dysfunction,
Barbiturates
INDICATIONS
antiepileptic,
sedative,
hypnotic
Barbiturates
SIDE EFFECTS
Resp depression,
bradycardia,
ataxia (FALL)
dependence & tolerance
(wean off to avoid withdrawal symptoms & seizure)
Only for short-term use (2 weeks or less)
REM rebound
(vivid dreams & nightmares),
hangover effect,
skin eruption,
constipation
paradoxical effects
Decreased effect of oral contraceptives (use a secondary method)
Barbiturates
CONTRAINIDCATIONS
pregnancy,
with other sedative-hypnotics (alcohol, opioids)
Barbiturates
SCHEDULE / ACTION
Long-acting:
schedule IV
Barbiturates
IS THERE A REVERSAL
NO REVERSAL AGENT
OFTEN REPLACED BY BENZOSSS
Barbiturates
THERAPEUTIC RANGE
Narrow therapeutic range
Benzodiazepines
MOA
MOA: GABA stimulation, Schedule IV
Benzodiazepines
INDICATIONS
Sedative (anxiolytic) => preventing alcohol withdrawal symptoms (DTs)
Epilepsy (antiepileptic)
Spasms (centrally acting
muscle relaxant)
Insomnia (hypnotic)
anesthesia induction (sedative/hypnotic)
Benzodiazepines
ROUTES
Routes: PO, IM, IV
Benzodiazepines
DRUGSSS
lorazepam
diazepam
chlordiazepoxide
- Prophylaxis for alcohol withdrawal,
- scheduled & PRN,
- long onset of action,
- safest Benzodiazepine
alprazolam
temazepam
clonazepam
midazolam
- pre-operative
Benzodiazepines withdrawal symptoms
anxiety, insomnia, diaphoresis, tremor, delirium, HTN, seizure
Anesthesia
Anesthetics Types & Routes
GENERAL
Inh/IV
General CNS depression
loss of consciousness,
amnesia
analgesia,
complete muscle paralysis,
loss of reflexes/ANS
Anesthesia
Anesthetics Types & Routes
REGIONAL
Injection close to a nerve
No loss of consciousness, no amnesia
Regional effects:
analgesia,
muscle paralysis,
loss of reflexes/ANS
Anesthesia
Anesthetics Types & Routes
LOCAL
Local analgesia
(dental procedures, minor surgeries)
Injection/topical
Inhalation Anesthetics
Inhaled gas: nitrous oxide (NO)
Inhaled volatile liquids:
isoflurane
Inhaled gas: nitrous oxide (NO)
Inhaled volatile liquids:
isoflurane
Fast induction
& fast reversal/recovery
no metabolism;
eliminated by ventilation
Inhaled gas: nitrous oxide (NO)
Inhaled volatile liquids:
isoflurane
REVERSAL AGENT
Reversal agent: deep breathing; intubation/ventilation
Inhaled gas: nitrous oxide (NO)
Inhaled volatile liquids:
isoflurane
ADVERSE EFFECTS
“Anesthesia awareness” (under-sedation)
Overdose:
respiratory depression,
hypotension,
brady-dysrhythmia
SIDE EFFECTS
HA,
confusion
N/V
Shivering/chills
malignant hyperthermia
dantrolene IV to treat malignant hyperthermia, watch for liver failure
malignant hyperthermia: severe adverse reaction to inhaled anesthesia and succinylcholine => severe temperature increase, severe muscle rigidity, death
dantrolene IV to treat malignant hyperthermia
IV Anesthetics
etomidate
propofol
ketamine
etomidate
propofol
ketamine
Rapid onsets and short durations of action
propofol
high risk of infection,
use vial within 6hrs
propofol
CONTRAINDICATION
Contraindication: allergy to egg/soybean
ketamine
SIDE EFFECT
Side effect (paradoxical effects)
cause hallucination,
delirium,
confusion
Other Drug used as IV Anesthetics
Benzodiazepines (-pam, -lam)
midazolam (Versed)
flumazenil to reverse
Opioid
morphine,
fentanyl
naloxone to reverse
Neuromuscular blocker (paralytics)
succinylcholine,
vecuronium
No analgesic effect
No sedative effect
succinylcholine has no reversal,
but very short-acting
neostigmine (cholinesterase-inhibitor) to reverse vecuronium
Regional Anesthesia
Anesthetic agent injected around nerves
(spine, local nerves)
no LOC
(loss of consciousness)
may need benzodiazepines
or
opioids for
sedative effect
Regional Anesthesia
MOA
Prevent conduction of nerve impulses at injection site
Motor,
Sensory,
Autonomic
Regional Anesthesia
ROUTES
Routes for regional anesthesia:
injection close to a nerve
Regional Anesthesia
SODIUM CHANNEL BLOCKER:
procaine
lidocaine
Regional Anesthesia
bottom notes
LOC: loss of consciousness
Reduces complication & expedites recovery, ambulation
We will use “sodium-channel-blocker” for seizure (phenytoin) and dysrhythmia but these are all similar yet different
Routes:
Epidural larger dose further away from the spine
Spinal (intrathecal/subarachnoid) smaller dose right beside the spine
Local conduction block (topical or superficial injection)
