CNS drugs depressants and stimulants

what are the three types of CNS drugs?

• Barbiturates

• Benzodiazepines

• Miscellaneous drugs

Sedative Hypnotics Low Doses

Calm the CNS without sleep

Sedative Hypnotics High Doses

Calm the CNS with sleep

Benzodiazepines

• Sedative-hypnotic, anxiolytic

• Non-benzodiazepines often used for sleep

• All drugs end in -zepam

• Increase GABA, do not suppress REM, do not increase metabolism

clinical use of benzodiazepines

Calming effect on CNS helps with seizures and sedation; used in alcohol withdrawal

adverse effects of benzodiazepines

• increased risk for falls

• Lethargy, dizziness, hangover effect (cloudy feeling)

Toxicity and Overdose of Benzodiazepines

• Symptoms: somnolence, confusion, coma, diminished reflexes

what is the antidote to an overdose of benzodiazepines

Flumazenil

interactions with benzodiazepines

• Grapefruit juice: Can increase CNS depression

• Caution with other CNS depressants (alcohol, opioids)

Barbiturates

• Can transition from therapeutic to toxic quickly

• Commonly used as antiepileptics

• Work on GABA

• More likely to cause respiratory issues and coma

• Notorious enzyme inducers; check med interactions

indications for barbituates

• Sedatives, anticonvulsants, anesthesia

• Drug names often end in -barbital or -exital

Adverse Effects of barbiturates

Vasodilation, drowsiness, lethargy, respiratory depression, cough

toxicity and overdose of barbiturates

• No reversal for overdose; manage with fluids, oxygen, pressor support

• Risk of uncontrollable seizures

drug interactions with barbiturates

Additive effects with other CNS drugs, warfarin

Muscle relaxants

• Indications: muscle spasms, MS, cerebral palsy

• Best used with physical therapy

toxicity of muscle relaxants

• Baclofen can be administered via a pump; no reversal for overdose

• Flexeril is the most common muscle relaxant.

adverse effects of muscle relaxants

Light-headedness, dizziness, drowsiness

Nursing Implications of CNS depressants

• Monitor BP, VS, ins and outs

• Avoid alcohol and other CNS depressants

• Be aware of rebound insomnia

• Ensure safety measures (side rails, bed alarms)

• Keep call light within reach

• Monitor therapeutic effects!

Amphetamines

Improve mental alertness

• Effects: mood elevation and euphoria

ADHD Medications

• Includes amphetamines, methylphenidates, atomoxetine

• Important: Monitor mental health

Narcolepsy Medications

• Modafinil, armodafinil

Nursing Implications of CNS stimulants

• Monitor weight and height

• Administer 30-45 minutes before meals

• Keep a journal of mental health

• ADHD meds are not needed all the time; use as required.

Anorexiants

• Treat obesity (BMI over 30)

• Examples: Phentermine (less common), Orlistat (lipase inhibitor, not a CNS stimulant)

Triptans

• Antimigraine drugs that cause vasodilation of blood vessels

• Monitor blood pressure (BP), heart rate (HR), liver function, EKG