CNS Depressants

Pharmacology

Sedative

drugs that have an inhibitory effect on the CNS to the degree that they reduce: Nervousness, excitability, irritability

Hypnotics

cause sleep

much more potent effect on CNS than sedatives

Sedative-hypnotics dose dependent→

Barbiturate → benzodiazepines → Miscellaneous drugs

CNS Depressants: Benzodiazepines

formerly the most commonly prescribes sedative-hypnotic drugs

• sedative-hypnotic

  • Anxiolytic (anti-anxiety)

work on GABA- A receptors

safer than barbiturates, needs more to OD, leads to falls

Benzodiazepines: effects

calming effect on the CNS

Useful in controlling agitation

inducing sleep

Benzodiazepines: Indications

Sedation

sleep induction

treatment of acute seizure disorders

treatment of alcohol withdrawal

Benzodiazepines contraindication

drug allergy

narrow-angle glaucoma- dilation of eyes

pregnancy ** - miscarriage/ preterm birth

can cause hangover effect

Benzodiazepines: adverse effects

cognitive impairment

vertigo (dizzy!!!)

lethargy

fall hazard for older adults

“Daytime sleepiness”

Benzodiazepines: Anxiolytics (anti-anxiety)

Alprazolam (Xanax) PO

diazepam (Valium) half-life 48 hours PO/ IM/ IV/ Rectal

lorazepam (Ativan) status epilepticus- seizure that never stops over 5 min, IM/ IV

Midazolam (Versed)- preop surgery/ reduces anxiety/ sedation- agitation PO/ Nasal/ Buccal/ IV/ IM/ can cause amnesia

Benzodiazepines: Hypnotics

temazepam (Restoril)- sleep

Triazolam (Halcion)-sleep,

causes you to sleep within 20-40 min- take an hour before going to bed, need 6-8 hours of sleep

Librium (chlordiazepoxide)

slow acting benzodiazepine, releases Gaba creating a calming effect. Acute symptoms of alcohol syndrome/

IV → PO

Side effects

drowsiness, dizziness, loss of muscle contraction

Adverse Effects

confusion, respiratory depression caused by ongoing use

When providing education to the patient on the use of
a benzodiazepine medication, the nurse will include
which information?
A. These medications have little effect on the
normal sleep cycle.
B. Using this medication may cause drowsiness the
next day.
C. It is safe to drive while taking this medication.
D. These drugs are safe to use with alcohol.

B. Using this medication may cause drowsiness the next day.

Benzodiazepines and Alcohol

DANGEROUS

both increase GABA activity in the brain

causes compounding effects that can cause you to stop breathing

Barbiturates MOA

site of action: brainstem (reticular formation)
by potentiating the action of GABA. nerve impulses traveling in the cerebral cortex are inhibited

short ac

Barbiturates Indications:

Short acting

sedation and control of seizure

Intermediate acting

Sedation and control of seizure

Long Acting

Seizure prophylaxis

Very narrow therapeutic window

Barbiturates Contraindications

pregnancy

significant respiratory difficulties

severe kidney or liver disease

caution in older adults- organs are in worse shape than someone who is younger

Barbiturates adverse effects

similar to benzo, but more severe

reduced REM sleep- agitation and inability to deal with normal stress

overdose frequently leads to respiratory depression and subsequent respiratory arrest

Barbiturate: Phenobarbital

prototypical

long acting

uses: prevention of generalized tonic-clonic seizures and febrile convulsions

alcohol withdrawal

rarely used as sedative- no longer used as hypnotic

Barbiturates have a low therapeutic index. How
does the nurse interpret this?
A. Low doses are most therapeutic
B. The toxic range is narrow
C. They are habit forming
D. The effective, safe dosage range is narrow

D. The effective, safe dosage range is narrow

MISC. Drugs Hypnotics

Nonbenzodiazepine: Eszopiclone (Lunesta)

first hypnotic to be FDA approved for long term use

binds to GABA receptors

instant effect

designed to provide a full 8 hours of sleep

more potent

longer half-life

Zolpidem (Ambien)

shorter acting

lower incidence of daytime sleepiness compared with benzodiazepine hypnotics

sleepwalking

Muscle Relaxants: MOA

Act to relieve pain associated with skeletal muscle spasms

Majority are centrally acting

-CNS is the site of action

-similar in structure and action to other CNS depressants

Direct acting

Muscle Relaxants: Indications

relief of painful musculoskeletal conditions

_muscle spasms (pregnancy, overuse, stroke)

_Management of spasticity of sever chronic disorders (multiple sclerosis, cerebral palsy)

works best when used along with physical therapy

Muscle relaxants: adverse effects/ Toxicity

adverse effects:

extension of effects on CNS and skeletal muscles

euphoria

drowsiness

muscle weakness

dry mouth

Toxicity

primarily involve the CNS

no specific antidote or reversal

can cause coma

avoid driving, (benzo) alcohol, confusion and falls, very addictive,

Common Muscle Relaxants

Baclofen (Lioresal)

used through pump → spinal fluid. allows for lower dosage

severe withdrawal symptoms, confusion, muscle spasms, sweating anxiety, with PT

should not suddenly stop

Cyclobenzaprine (Flexeril)

deep sedation

Carisoprodol (Soma)

Methocarbamol (Robaxin)

AT risk for fall because cause hyoptension

Which statement regarding muscle relaxants does the nurse identify as
being accurate?
A. Baclofen (Lioresal) is available as an injectable form for use with an
implantable pump device.
B. Cyclobenzaprine (Flexeril) produces little sedation.
C. Patients taking muscle relaxants are at high risk of developing
hypertension.
D. Patients taking muscle relaxants should be told to stop taking the
medication if they feel sleepy

A. Baclofen (Lioresal) is available as an injectable form for use with an implantable pump device

Nursing implications: CNS Depressants

give hypnotics 30-60 min before bedtime for maximum effectiveness in inducing sleep

most benzos cause REM rebound and a tired feeling the next day; use with caution in older adults

instruct patients to avoid alcohol and other CNS depressants

rebound insomnia may occur for a few nights after a 3-4week regimen has been discontinued

safety is important

Physchotherapeutic Drugs

3 main types

antianxiety

antidepressant

antpsychotic

Antidepressant Drugs Indications & MOAs

Indications
▪ Major depressive disorders
▪ Eating disorders
▪ Personality disorders
▪ Various medical conditions

Mechanism of Action
▪ Increase the levels of neurotransmitter
concentration in CNS

Most common antidepressant

SSRIs- selective serotonin reuptake inhibitors

Antidepressants: Classes

selective serotonin reuptake inhibitors (SSRI’s)

tricyclic antidepressants- (TCA’s)

Monoamine oxidase inhibitors (MOAI’s)

Second generation/ SSRI’s MOA

Fewer adverse effect than TCAs and MOAIs

very few drug-drug or drug-food interactions

still take about 4 to 6 weeks to reach maximum clinical effectiveness

now considered first-line drugs for depression

MOA

inhibition of serotonin reuptake and possible effects on norepinephrine and dopamine reuptake

SSRI adverse effects

insomnia

weight gain

sexual dysfunction (erectile)

Serotonin syndrome READ BOOOK ***

Common symptoms

insomnia, headache, sexual dysfunction, nausea, dizziness, sweating, agitation, restlessness, clonus (rhythmic muscle spasm), tremor, rash, dry mouth, ocular clonus, confusion, delirium, hyperreflexia, loss of consciousness, high BP,

Late symptoms: seizures, rhabdomyolysis (muscle pain, weakness, dark urine, feeling tired, severe muscle cramps, confusion), renal failure, death

Commonly used SSRI

Citalopram (Celexa)

fluoxetine (Prozac)

duloxetine (Cymbalta)

mirtazapine (Remeron) - sedation occurs, give at HS,

Sertraline (Zoloft)

Escitalopram (Lexapro)

Tricyclic antidepressants MOA

Block reuptake of neurotransmitters, causing accumulation at the nerve endings

2nd line medications

Tricyclic indications

Depression

OCDs (clomipramine)

Pain

Tricyclic

amitriptyline

desipramine

doxepin

imipramine

nortriptyline

protriptyline

TCAs can be added to

pain medication because it gets a better synergistic effect

trigeminal neuralgia

intense pain in the face

dehabilit

TCA no no

NO PREGNANCY

sedation (geriatric shouldn’t need)

impotence (Erectile dysfunction)

orthostatic hypotension

TCA overdose

Lethal: 70%-80% die before reaching the hospital

CNS and cardiovascular systems are mainly affected

no specific antidote

death from seizure or dysrhythmia

activated charcoal-

alkaline promoting food

sodium bicarbonate, fruits and vegetable

MOAIS

rarely used for depression

used for Parkinson’s disease

disadvantage: potential to cause hypertensive crisis when taken with tyramine

ingestion of food or drinks with tyramine leads to hypertensive crisis, which may lead to cerebral hemorrhage, stroke, coma, or death (aged cheese, smoked, pickled or aged meats, sausage, yeast extracts, red wines, bologna)

avoid foods that contain tyramine

MAO Inhibitors READ*

-Nardil- NO

-Parnate- POPULAR

-Marplan- MEDS

barbiturates

tricyclic antidepressants

antihistamines

CNS depressants

antihypertensives

OTC cold medication

causes sweating, tremors, elevated temp, bounding heart, high BP

Antidepressant Nursing Implications

Inform patients that it may take several weeks to see
therapeutic effects.
▪ Monitor patients closely during this time, assess for
suicidal tendencies and provide support.
▪ Assist older adult and weakened patients with
ambulation and other activities because falls may
occur because of drowsiness or postural
hypotension.
▪ Caffeine and cigarette smoking may decrease
effectiveness of medication therapy.
▪ With MAOIs, instruct patients and family regarding
tyramine-containing foods and signs and symptoms
of hypertensive crisis.

When patients are taking selective
SSRIs for the first time for
depression, which is most important
to monitor for during the first few
weeks of therapy?
A. Hypertensive crisis
B. Suicidal thoughts
C. Convulsions
D. Orthostatic hypotension

B. Suicidal Thoughts

Antipsychotics

First Generation

Haloperidol (Haldol)

Chlorpromazine (Thorazine)

thioridazine (Mellaril)

Second Generation

Aripiprazole (Abilify)

Brexpiprazole (rexulti)

Clozapine (Clozaril)

Lurasidone (Latuda)

Quetiapine (Seroquel)

Ziprasidone (Geodon)

Olanzapine (Zyprexa, Lybalvi, Symbyax)

Antipsychotics MOA

dopamine levels in CNS are decreased

drug-induced psychoses, schizophrenia, and autism

used to treat extreme mania

BLACK BOX

dementia

Adverse effects:

CNS effects

-drowsiness

-neuroleptic malignant syndrome (NMS)

_ potentially life threatening

_high fever, unstable blood pressure (BP), myoglobinemia

-Extrapyramidal symptoms (EPS): pseudo parkinsonism-akathisia

-tardive dyskinesia

Weight Gain (abdominal obesity)

Metabolic Syndrome

Antipsychotic typicals

much more side effects

EPS

older drugs

higher tardive dyskinesia risk

Antipsychotic atypicals

Newer drugs

treats psychosis, bipolar, depression,

more likely to cause weight gain, diabetes

lower tardive dyskinesia risk

Antipsychotics Nursing Implications

monitor for therapeutic effects

monitor for adverse effects

advise patients to avoid abrupt withdrawal

antiparkinsonian drugs

chronic, progressive, degenerative disorder

affects dopamine-producing neurons in the brain (affects movement)

slowness of gait, droopy face, no expression, slow movements

antiparkinsonian drugs: symptoms of PD

Classic symptoms include:

-tremor

-rigidity

-akinesia

-postural instability

-TRAP acronym

Staggering Gait

Drooling

Dopamine Replacement Drugs

Carbidopa-Levodopa (Sinemet)

Given with Carbidopa

Adverse effects:

delay use as long as possible because it only goes so far

causes lots of nausea

cardiac dysthymias

GI distress

muscle cramps

all about function

empty stomach!!

Antiparkinsonian Drugs: Nursing Implications

-Inform patient not to take other medications with PD drugs
- Administer oral doses with food to minimize GI upset.
- Encourage patient to force fluids to at least 3000 mL/day (unless contraindicated).
- Taking levodopa with MAOIs may result in hypertensive crisis.
- Patient should be taught not to discontinue antiparkinson drugs suddenly

hyperpyrexia syndrome- febrile, neurological emergency

PHC