Chapter 13 (Watkins) Nervous system Medications

Acetaminophen

(Tylenol) decreases pain and fever, but it has no anti-inflammatory effect. often an ingredient in combination products such as to relieve pain or things like NyQuill Because of minimal side effects it is used frequently combined with narcotics, such as oxycodone with acetaminophen (Percocet), to treat moderate to severe pain. Excessive use can cause liver damage

Cholinergic Nerve Cell

A nerve cell that releases acetylcholine, which relaxes the body.

Adrenergic Nerve Cell

A nerve cell that releases epinephrine or norepinephrine, which excite the body.

Review Question: The disease most commonly associated with a drug holiday is...? A. Parkinson's disease B. Alzheimer's disease C. Myasthenia gravis D. Fibromyalgia

A. Parkinson's disease

General Anesthesia

Administered by Intravenous (IV) infusion or inhalation. For longer procedures an IV agent like midazolam (Versed), propofol (Diprivan), or ketamine (Ketalar) may be used initially, followed by inhalation therapy with medications such as deflurane (Suprane), isoflurane (Forane), or sevoflurane (Ultane) Inhaled anesthesia are volatile agents that can depress respiratory and cardiovascular functions

Mood Stabilizers

Also called antimanic agents. stabilize the extreme mood shifts seen in patients with bipolar disorder and are also used in patients with schizophrenia Example: lithium (lithium is a salt so very important for patients to not become dehydrated while taking lithium) has a small therapeutic window. Lithium toxicity can be fatal, blood lithium assays (levels) must be performed regularly. Signs of Toxicity: drowsiness, blurred vision, confusion, sensitivity to light, tremors, muscle weakness, cardiovascular collapse, seizures, and coma Other Examples: lamotrigine (Lamictal), and valproic acid (Depakene, Depakote)

Parasympathomimetic Drugs

Also known as cholinergic, drugs that stimulate the parasympathetic nervous system calm the nervous system Mimic the action of the parasympathetic nervous system; cholinergics release acetylcholine, which relaxes the body's flight-or-flight mechanism. Rarely used because they severely slow body body system activity and constrict respiratory passages One of the few cholinergic drugs still used is pilocarpine (Pilopine) for the treatment of open-angle glaucoma. Example: Nerve gases

Psychotropic drugs

Any medication that affects the mind, emotions, or behaviors

Opioid Analgesics

Are strong painkillers that suppress the CNS excellent choice when pain cannot be relieved by milder drugs. The active ingredient in most narcotics is opium, can by synthetic or semisynthetic can cause severe side effects, can also slow respirations to dangerous levels Narcan can be given to reverse opioid analgesic effects. Narcotics produce euphoria, or happy feelings, they can cause physiological or psychological dependence, very addictive

Review Question: The classification of drugs usually used for surgical procedures is...? A. Benzodiazepines B. Anesthetics C. Barbiturates D. Beta blockers

B. Anesthetics

Review Question: Which type of anesthesia has a high risk for allergic reaction? A. Amides B. Esters C. Both A and B D. None of the above

B. Esters

Medications for Dementia

Cholinesterase inhibitors are the drugs of choice, even though it is unclear how they work, in treating mild to moderate Alzheimer's disease. Research shows these drugs prevent the breakdown of cholinesterase in the brain that is responsible for memory and thinking. Dementia is a progressive, irreversible decline in mental function. Alzheimer's disease is the most common cause of Dementia. The goal of these meds are to prevent or slow further mental deterioration. best outcome is early diagnosis, so treatment can begin.

Review Question: The classification of drugs usually used for treating psychosis is...? A. SSRIs B. EEGs C. Benzodiazepines D. Neuroleptics

D. Neuroleptics

Tricyclic Antidepressants (TCAs)

Help electrical impulses cross the synapse Still the drug of choice for severe depression and inpatient depression, despite many more side effects

Non-steroidal Anti-Inflammatory Drugs (NSAIDs)

In the context of pain and fever relief, refer to medications such as ibuprofen (Motrin & Advil) Reduce pain and swelling caused by inflammation NSAIDs can be combined with narcotics to relieve moderate to severe pain Excessive use can cause kidney damage

Central Nervous system (CNS)

Includes the brain and spinal cord, which contain billions of neurons.

Monoamine Oxidase Inhibitors (MAOIs)

Inhibit MAO, an enzyme that terminates the action of neurotransmitters at the synapse. improves the retention of neurotransmitters at the site requires dietary exclusion of foods containing tyramine

Blood-Brain-Barrier

It is the barrier in the brain that prevents toxic substances and some medications from entering the brain. Most of these types of drugs are powerful enough to cross this barrier

Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)

Newest category of mediations to treat depression block the reuptake of both serotonin and norepinephrine Increase in these levels are shown to elevate the mood Examples: venlafaxine (Effector XR), desvenlafaxine (Pritiz), and duloxetine (Cymbalta)

Medications for Parkinson's Disease

Parkinson's disease is a degenerative disorder of the CNS. When neurons that produce the neurotransmitter dopamine die, the muscle movements become disorganized. Antiparkinsonian drugs focus on keeping dopamine and acetylcholine at the nerve synapse and thereby promote the transmission of nerve signals Classified as dopaminergic (replacing or increasing dopamine) Examples: selegiline (Eldepryl), bromocriptine (Parledel), ropinirole (Requip), and carbidopa/levodopa (Sinemet)

Selective Serotonin Reuptake Inhibitors (SSRIs)

Prevent serotonin from being used up at the synapse low serotonin levels have been implicated in depression, and keeping serotonin at the synapse improves mood Because they have so few side effect, they are often the first class of drug prescribed for depression. Example: citalopram (Celexa), fluoxetine (Prozac), paroxetine (Paxil), and sertaline (Zoloft)

Esters (local anesthetics)

Procaine and tetracaine have potential for severe allergic reactions such as anaphylactic shock because of the release of para-aminobenzoic acid (PABA), a known allergen, during metabolism process Esters are limited to topical preparations to limit PABA issues

Alcohol Interaction with Medication

Rarely prescribed as a medication, however because it interacts with other medications and can have powerful effects on the body it is included in this chapter. Alcohol added to medication can cause confusion, peripheral vasodilation, increased heart rate, electrolyte imbalances, decreased motor coordination, unsteady gait, and slurred speech Treatment includes disulfiram (Antabuse), behavior modification, vitamin B injections, and dietary changes. Should be assessed for respiratory problems, vomiting, convulsions, cerebral swelling, electrolyte imbalances, and tremors when they are withdrawing from alcohol

Anxiolytic Medications

Reduce the intensity of fears, dangers and or tension that a patient may be experiencing Can be taken routinely or only when the patient feels increasing anxiety. These drugs work in the limbic system of the brain by depressing the subcortical levels of the CNS and have a calming effect Can range from mild sedation to coma, depending on dosage and medication May not work as quickly as CNS depressants, but have very little dependence issues. Two types: Benzodiazepines and Barbiturates

Insomnia Medications

Sometimes barbiturates are used to induce sleep by depressing the CNS Used to relax patients before a minor procedure or general surgery Other newer non-narcotic benzodiazepine hypnotics such as zolpidem (Ambien) and eszopiclone (Lunesta) help to promote sleep with fewer side effects. these newer non-narcotic medications are able to target just the areas promoting sleep without depressing the entire CNS Addiction risk, used on a limited basis

Salicylates

Such as aspirin, relieve mild to moderate pain and reduce inflammation and fever. Used to decrease inflammation in blood vessels, to improve cardiovascular flow. Disadvantage: causing GI distress, and should not be used in children with viral infections because of the danger of Reye's syndrome

Hydantoins

Such as phenytoin (Dilantin) delay sodium from crossing the neural membranes, this effect decreases the potential for too much electrical activity and calms the cell Are the drug of choice for tonic-clonic (grand mal) and partial seizures

Medications for Treating Psychoses

These meds are called Antipsychotics or neuroleptics Psychoses comprise a class of disorders characterized by abnormal thoughts, disorganized communication, and lack of interaction with the environment. Delusions, hallucinations, paranoia, and bizarre thoughts and behaviors Treat the abnormal actions and behaviors of psychoses such as talking and interacting with a situation that only patients can see and hear. Some antipsychotics are used for nausea and vomiting, dementia, agitation, and spasms, be sure to know why neuroleptics were prescribed.

Gamma-aminobutyric acid (GABA)

a neurotransmitter inhibitor, in other words, GABA inhibits abnormal electrical activity in the brain, and an increased presence of this amino acid decreases seizure activity. Example: vigabatrin (Sabril), and diazepam (Valium), lamotrigine (Lamictal), tiagabine (Gabitril), topiramate (Topamax), and carbamazepine (Tegretol)

Methylsalicylate

a topical anti-inflammatory medication used to irritate the surface of the skin. This irritation increases blood flow to the area where it was applied and thus decreases pain. An example of this is Bengay

Alpha Blockers

affect vascular smooth muscle and are used to alleviate hypertension and benign prostatic hypertrophy Examples: alfuzosin (Uroxatral), doxazosin (Cardura), prazosin (MInipress), tamsulosin (Flomax), and terazosin (Hytrin)

Sympathomimetic drugs

also called adrenergic agonists, are autonomic drug that stimulates the nervous system when the body needs to be excited. They work to stimulate the heart, increase the blood flow to the skeletal muscles, and constrict peripheral blood vessels, which then dilate certain parts of the body Used to restore heart rhythm during cardiac arrest and to increase blood pressure in cases of shock They constrict constrict capillaries if the patient is bleeding. Major contraindication is hypersensitivity to the drug. Should be used cautiously in patients with hypertension, myocardial infarction, atrial fibrillation, or hypovolemia, in children, and in women who are pregnant or breastfeeding

Barbiturates

an older style of medication including phenobarbital, which are not often used due to high levels of addiction and a very narrow window of effectiveness before serious problems occur. May still be used to control seizures

Local Anesthesia

applies to the body's surface to numb and area before an procedure blocks entry of sodium ions into nerve fibers adequate amount must be applied to keep the area numb throughout the entire procedure Routes: Cream, aerosol spray, otic or ophthalmic drops, or an injectable solution. Classified as esters or amides

Neurotransmitters

are chemicals that facilitate the movement of messages across the synapses.

Benzodiazepines

are used for anxiety, seizures, alcohol withdrawal symptoms, and muscle relaxation Can also be used to reduce anxiety before general anesthesia Examples: lorazepam (Ativan), diazepam (Valium), and alprazolam (Xanax)

Central Nervous System Stimulants

are used to treat ADD, ADHD, obesity, and sleep disorders such as narcolepsy calm patients and increase their ability to focus used to increase metabolism for obese patients Patients with ADD and ADHD are being bombarded by a multitude of stimuli and is unable to focus on any one of them, CNS stimulants help patients focus on a few stimuli Example: (adderall), pemoline (Cylert), and methylphenidate (Ritalin)

Nervous System Medications

are used to treat pain, anxiety, depression, mania, insomnia, convulsions, and schizophrenia. Work by either exciting or depressing the CNS

Adrenergic Blockers

block the action of adrenergic and thus have a parasympathetic effect. calms the nervous system useful for treating cardiac arrhythmias, high blood pressure, migraine headaches, and chest pain because they slow the heart rate, relax the blood vessels, and allow blood to flow more freely, thus decreasing the workload on the heart. Broken down into two groups: Alpha blockers and Beta blockers

Peripheral Nervous System (PNS)

consists of the somatic (voluntary) and autonomic (involuntary) nervous systems.

The Somatic Nervous Systems

consists of those muscles over which we have conscious control (ex. for lifting your arm to scratch your nose)

The Autonomic Nervous System

controls our internal organs and glands Broken down into 2 parts: sympathetic and parasympathetic

sympathetic nervous system

controls the body's "fight or flight" response

Synapse

gap between nerves, where most nervous system drugs act, and can adjust the transmission of messages by neurotransmitters.

parasympathetic nervous system

helps the body to relax

Anticholinergics or Cholinergic Blockers

inhibit the parasympathetic branch of the autonomic nervous system and thus promote flight-or-flight symptoms These drugs dry secretions, including those in the respiratory tract, and are used for asthma and motion sickness. used for preoperative relaxation, for neuromuscular blocking of spasms, as antidotes to insect stings, and in cholinergic crises. Example: atropine (Atropen)

Anesthesia

means loss of sensation Anesthesia administered locally crates a lack of feeling without a loss of consciousness General Anesthesia causes patients to lose both feeling and consciousness, such as during a surgical procedure.

Antidepressants

preserve neurotransmitters at the synapse some patients have to try numerous medications before they find an antidepressant that works for them and has tolerable side effects Four categories of antidepressants: Monoamine Oxidase Inhibitors (MAOIs), Tricyclic Antidepressants (TCAs), Selective Serotonin Reuptake Inhibitors (SSRIs), Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs)

Analgesics

reduce pain without eliminating feeling or sensation, as occurs with anesthetics. Examples: salicylates, acetaminophen, non-steroidal anti-inflammatory drugs (NSAIDs), and narcotics.

Other examples of anxiolytics

selective serotonin reuptake inhibitors (SSRIs), such as celexa (citalopram), Fluoxetine (Prozac), and sertraline (Zoloft) Serotonin-norepinephrine reuptake inhibitors (SNRIs) such as venlafaxine (Effexor XR) and tricyclic antidepressants such as amitriptyline (Elavil)

Amides (local anesthetics)

such as lidocaine or novocaine, tend to last longer, so they are more popular Adverse affects and allergies are rare Patient must be observed during procedure to make sure area is numb throughout and monitor any negative reactions

Beta Blockers

work by blocking the effects of the hormone epinephrine. This action affects the heart and blood vessels and causes the heart to beat more slowly and with less force, thereby reducing blood pressure. Examples: acebutolol (Sectral), atenolol (Tenormin), bisoprolol (Zebeta), metoprolol (Lopressor), nadolol (Corgard), nebivolol (Bystolic), and propranolol (Inderal LA)