Pregnancy catagories

• The FDA has a categorization of drug risks to the fetus that runs from: "Category A" (safest) to "Category X" (known danger--do not use!)

Category A

• Controlled studies in women fail to demonstrate a risk to the fetus in the first trimester (and there is no evidence of a risk in later trimesters), and the possibility of fetal harm appears remote.

Category B

• Either animal-reproduction studies have not demonstrated a fetal risk but there are no controlled studies in pregnant women, or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the first trimester (and there is no evidence of a risk in later trimesters).

Category C

• Either studies in animals have revealed adverse effects on the fetus (teratogenic or embryocidal or other) and there are no controlled studies in women, or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the fetus.

Category D

• There is positive evidence of human fetal risk, but the benefits from use in pregnant women may be acceptable despite the risk (e.g., if the drug is needed in a life-threatening situation or for a serious disease for which safer drugs cannot be used or are ineffective).

Category X

• Studies in animals or human beings have demonstrated fetal abnormalities, or there is evidence of fetal risk based on human experience or both, and the risk of the use of the drug in pregnant women clearly outweighs any possible benefit. The drug is contraindicated in women who are or may become pregnant.

**Effects of drugs on the CNS

• What is the CNS?• Organ system that

consists of the brain & spinal cord

PNS

• What is the PNS?• Peripheral Nervous

system• It connects the CNS to

other body parts

CNS stimulants

• Sympathomimetics• Used to treat ADHD,

narcolepsy and obesity• Highly addictive!!

Sympathomimetics

Adverse effects• Headache• Palpitations• Cardiac dysrhythemias• Hypertension• Nervousness• nausea

Contraindications & Interactions

• History of drug abuse• Severely agitated• Hyperthyroidism• Diabetes mellitus• Moderate to severe

hypertension• Advanced arteriosclerosis• Angina pectoris• glaucoma

Sympathomimetics

• Important points patients should know:• Advise patients taking CNS stimulants for a

prolonged period, withdrawal symptoms could occur.

• A gradual decrease is essential to prevent withdrawal effects.

Anxiety • Very common disorder• Signs of anxiety are:• Excessive, ongoing worry and tension• An unrealistic view of problems• Restlessness or a feeling of being "edgy"• Irritability• Muscle tension• Headaches• Sweating• Difficulty concentrating• Nausea• The need to go to the bathroom frequently• Tiredness• Trouble falling or staying asleep• Trembling• Being easily startled

•

What causes anxiety?• The exact cause of GAD is not fully known, but a number of factors --

including genetics, brain chemistry and environmental stresses -- appear to contribute to its development.

• Genetics: Some research suggests that family history plays a part in increasing the likelihood that a person will develop GAD. This means that the tendency to develop GAD may be passed on in families.

• Brain chemistry: GAD has been associated with abnormal levels of certain neurotransmitters in the brain. Neurotransmitters are special chemical messengers that help move information from nerve cell to nerve cell. If the neurotransmitters are out of balance, messages cannot get through the brain properly. This can alter the way the brain reacts in certain situations, leading to anxiety.

• Environmental factors: Trauma and stressful events, such as abuse, the death of a loved one, divorce, changing jobs or schools, may lead to GAD. GAD also may become worse during periods of stress. The use of and withdrawal from addictive substances, including alcohol, caffeine, and nicotine, can also worsen anxiety.

***Benzodiazepine• Medication: Drugs are available to treat GAD and may be especially

helpful for people whose anxiety is interfering with daily functioning. The medications most often used to treat GAD in the short-term are from a class of drugs called benzodiazepines. These medications are sometimes referred to as "tranquilizers," because they leave you feeling calm and relaxed. They work by decreasing the physical symptoms of GAD, such as muscle tension and restlessness. Common benzodiazepines include Xanax, Librium, Valium and Ativan. Antidepressants, such as Paxil, Effexor, Prozac, Lexapro, and Zoloft, are also being used to treat GAD. These antidepressants may take a few weeks to start working but they're more appropriate for long-term treatment of GAD.

• Used a hypnotic

***Antipsychotics

• Neuroleptic drugs that can improve thought disorders

Seizures

• What is a seizure?• Abnormal electrical

activity in the brain.

• Diazepam (Valium) is given to stop the repetitive seizure activity, and then, long-acting drugs such as phenytoin (Dilantin) are given to prevent the recurrence of seizures

Did you Know?

• Treatment for lice effects the CNS and causes the lice to have seizures, so these types of drugs are not recommended for people with seizure disorders

Barbiturates

• Classified as CNS agents,

anticonvulsants and sedative-hypnotic drugs.

How are they used?• Primarily used to treat

insomnia• Partial epilepsy• Tonic clonic seizures

***Insomnia

• Inability to sleep • Previously Barbiturates were used to treat insomnia

Epilepsy

Types of seizures• Tonic clonic seizures -

Previously termed grand-mal seizures

• Generalized absence seizures- previously called petit mal

• Generalized myoclonic seizures

• Partial seizures

Some causes of Epilepsy• Epilepsy is a permanent,

recurrent seizure disorder.• Brain injury at birth• Head injuries• Inborn errors of metabolism• Some patients the cause is

never determined

Antiseizure drugs (Anticonvulsants)

• Phenytoin-Dilantin• Diazepam-Valium• Lorazepam-Ativan• Phenobarbital-Barbital• Carbamazepine-

Tegretol• Valproate-Depakote• Valproic acid-Depakene

**Phenytoin (most common drug in the hydantoin group)

Interactions with this drug• Antacids• Antidiabetic agents• Antipsychotics• Barbiturates• Calcium channel blockers• Corticosteroids• Estrogens• Oral contraceptives• Antidepressants• Vitamin D analogues

Important points patients should know:

• Urine might become discolored to a pink or red-brown color.

• Blood glucose levels should be checked more closely because phenytoin can inhibit insulin release.

***Valproic acid (Depakote)

How is it used?• Management of absence

and mixed seizures• Mania• Migraine headache

prophylaxis• Most common drug of

choice for childhood absence seizures

Important points patients should know

• May irritate the mouth, throat and stomach

• Take with meals or snacks to reduce stomach upset

**Atropine

• Patients receiving atropine should be encouraged to use frequent mouth rinses, gum or candy to relieve dry mouth.

Parkinson’s Disease

What is it?• Nervous system disorder

characterized by movement abnormalities such as tremor of the extremities and head, and great difficulty in coordination of fine muscle movement.

• Lack of dopamine in the brain

Signs of the disease• Slowness in initiating

movement• Shuffling gait • Skeletal muscle rigidity

**Michael J. Fox

• At this time there is no cure for Parkinson's disease

• The cause is unknown

Drugs to treat Parkinson's disease

• Levodopa- approved in 1970 and is the most commonly used drug to date for treatment of Parkinson's disease

• Levodopa readily crosses the blood-brain barrier, unlike dopamine.

Dopanimergic Drugs

Adverse effects• Dyskinesia- is a movement

disorder which consists of effects including diminished voluntary movements and the presence of involuntary movements

• Hallucinations• Mental confusion

Important points patients should know• Levodopa may discolor urine

and perspiration• Avoid foods rich in Vitamin B6

such as beans and cereal.• Regular dental checkups are

needed to prevent dental problems caused by inhibition of salivation.

• Rebound of parkinsonism can occur if medication stops abruptly.

***Parkinsonism

• The symptoms that are produced by certain drugs, poisons, and traumatic lesions in the basic ganglia

Schizophrenia

What is it?• One of the most common

psychotic disorders• Cause is unknown• Hearing or seeing things

that are not real• Distortions of thought

process• delusions

Negative symptoms include:• Social withdrawal• Anhedonia (the inability to

experience pleasure)• Apathy• This illness is chronic• Less than 20% of patients

recover fully from a single episode of psychosis

****Antipsychotic drugs

How are they used?• Schizophrenia• Antiemetic• Antinausea agents

Adverse effects• Sedation• Dry mouth• Sexual dysfunction• Akathisia-difficulty in

initiating muscle movement• Bradykinesia• Tardive Dyskinesia-slowed

ability to make voluntary movement

Antipsychotic drugs

• Haloperidol-Haldol• Aripiprazole-abilify• Olanzapine-zyprexa• Quetiapine-zyprexa• Quetiapine-seroquel• Risperidone-risperdal

Depression

• One of the most common psychiatric disorders in the United States

• Symptoms include:• Feeling of doom• Lack of self worth• Inability to sense pleasure• Inability to concentrate• Changes in sleep

Antidepressant drugs

• Amitriptyline- Elavil• Citalopram-celexa• Fluozetine-prozac• Paroxetine-paxil• Sertraline-zoloft

MAOIs• Are second or third line

antidepressants because of the numerous interactions with prescriptions and OTC medications, as well as with certain foods and beverages.

• Cheese• Sour cream• Yogurt• Chicken liver• Beef• Coffee• Tea • Caffeinated sodas• Chocolate • Soy sauce• Figs• Raisins• Bananas and raspberries

***What is a sedative drug?

• A drug that diminishes the activity of the CNS

Effects of drugs on the ANS• The ANS regulates: Muscles – in the skin (around hair follicles; smooth muscle) – around blood vessels (smooth muscle) – in the eye (the iris; smooth muscle) – in the stomach, intestines and bladder (smooth muscle) – of the heart (cardiac muscle)

• Glands • The ANS is divided into three parts: • The sympathetic nervous system • The parasympathetic nervous system • The enteric nervous system.

ANS• The organs (the "viscera") of our body, such as the

heart, stomach and intestines, are regulated by a part of the nervous system called the autonomic nervous system (ANS). The ANS is part of the peripheral nervous system and it controls many organs and muscles within the body. In most situations, we are unaware of the workings of the ANS because it functions in an involuntary, reflexive manner. For example, we do not notice when blood vessels change size or when our heart beats faster. However, some people can be trained to control some functions of the ANS such as heart rate or blood pressure.

ANS

• The ANS is most important in two situations: • In emergencies that cause stress and require

us to"fight" or take "flight" (run away) and

• In nonemergencies that allow us to "rest" and "digest."

**Sympathetic nervous system

• It is a nice, sunny day...you are taking a nice walk in the park. Suddenly, an angry bear appears in your path. Do you stay and fight OR do you turn and run away? These are "Fight or Flight" responses. In these types of situations, your sympathetic nervous system is called into action - it uses energy - your blood pressure increases, your heart beats faster, and digestion slows down

The Parasympathetic Nervous System

• It is a nice, sunny day...you are taking a nice walk in the park. This time, however, you decide to relax in comfortable chair that you have brought along. This calls for "Rest and Digest" responses. Now is the time for the parasympathetic nervous to work to save energy - your blood pressure decreases, your heart beats slower, and digestion can start

**Alpha2-receptors

• Are often used to reduce blood pressure

Parasympathetic

Enteric nervous system

• Ever had diarrhea when you felt frightened? Had a stomach cramp before an important exam? Seen a snake barf a beetle meal when surprised?

• If you've answered 'yes' to any question in this little quiz, you've already noticed the handiwork of an obscure piece of neurological networking called the enteric nervous system.

Sympathomimetic Drugs

• Dopamine- used to treat shock• Epinephrine- asthma, cardiac arrest• Norepinephrine-shock• Clonidine-hypertension• Albuterol-asthma• Amphetamine-narcolepsy, ADD, obesity

***Cholinergic receptors

• Cholinergic receptors that affect the skeletal muscles are nicotinic receptors

• The nicotine molecule is very similar in shape to the neurotransmitter acetylcholine, which affects many bodily functions, including breathing, heart rate, learning and memory. Acetylcholine in turn also affects other neurotransmitters that have influence over appetite, mood, and memory. When nicotine gets into the brain, it attaches to nerve cells in places where acetylcholine would, creating the same effects.

Ecstasy and the ANS• Ecstasy is an illegal drug known as 3,4, MDMA

are Adam, XTC, Doves, or just E. • Originally patented as an appetite suppressant• Data now shows that MDMA may be toxic to the

brain• Studies have shown a 20 to 60% reduction in

healthy serotonin cells in the brains of MDMA users, damaging their ability to remember and to learn.

• Test on monkeys showed that brain damage was visible 7 years after they were given MDMA

Ecstasy

**Drug cautions

• Many drugs discussed in this chapter can cause dizziness, and patients are strongly advised to be careful when making changes in body position.

**Anesthetic Agents

1840’s surgical anesthesia became possible with the introduction of three agents:

ChloroformEtherNitrous oxideThese three agents when inhaled quickly, led to

unconsciousness

**What is anesthesia?

• Loss of sensation and or consciousness

Stages of Anesthesia

• Stage 1: Analgesia- pain is the first sense to be abolished, and consciousness is still retained.

• Sense of hearing is often enhanced in this stage

**Stage 2

• Excitement- this stage may not be a pleasant time of anesthesia.

• The patient more or less unconscious, can suffer from shaking and become violent.

• Sense of extreme fear may be felt, which can produce a phobic response to any suggestion of anesthesia.

• The passage from stage 1 to 3 needs to be attained quickly as possible.

• Sudden death can occur during stage 2 due to vagal nerve inhibition which extends from the cranium to the abdomen.

Stage 3

• Surgical anesthesia- Muscular relaxation occurs

• An endotracheal tube is passed into the trachea, which is connected to the respirator.

• The gag reflex is one of the last reflexes to disappear before stage 4 is reached

Stage 4

• Medullary paralysis- This stage begins with respiratory failure and can lead to circulatory collapse

• This stage is avoided• If it is reached it is called anesthetic accident.

**Pre-operative medications

• Preanesthetics- given 45-70 minutes before scheduled surgery.

• Valium-Benzodiazepine• Ativan-Benzodiazepine• Demerol- Opiod Analgesics• Morphine-Opiod Analgesics• Prevacid-Gastric Acid Pump Inhibitors• Reglan-Antiemetics

Inhalation Anesthetics

• Inhalation anesthetic agents are either volatile liquids (easily vaporized) or gasses.

• Nitrous oxide (laughing gas) Trade name is Entonox

Intravenous anesthetics

• Fentanyl• Propofol-Diprivan• What Michael Jackson

died from

Local anesthetics

Esters• Cocaine-topical• Novocain-SubQ

Amides• Lidocaine-epidural, topical• Marcaine- IM local

infiltration sympathetic block, lumbar epidural, caudal block

Specific applications

• Topical Anesthesia• Placement of a nerve

conduction blocking agent onto a tissue layer (skin or mucous membrane).

• This method is used to provide anesthesia on mucous membranes of the urethra, vagina, rectum, and skin

**Specific applications

• Cryoanesthesia- localized cooling

**General Anesthetics

• Anesthetics normally used to produce loss of consciousness before and during surgery are known as general anesthetics

Specific applications

• Local infiltration anesthesia

• Blocks nerves and area about to be operated on

• Sutures• Mole removal• Chest tubes

**Specific Applications

• Field Block Anesthesia• Affects a single nerve or

a network of nerves• subcutaneous injection

of a local anesthetic in an area bordering on the field to be anesthetized

• Spinal Anesthesia-• Gynecological• Obstetrical• Orthopedic• Genitourinary surgery• Injected into the

subarachnioid space

**Specific applications

• Epidural Anesthesia- involves injection of the local anesthetic into the epidural space via a catheter that allows repeated infusions.

• Used in labor & delivery

• Patients should be advised to lay flat for approximately 12 hours following a spinal block or epidural to prevent the leakage of cerebrospinal fluid, which may increase the risk of post anesthetic headaches

**Regional Anesthetics

• Affects a larger (but still limited) part of the body compared to local anesthetics, and is often used in obstetrics (Labor & delivery).

**After Anesthesia

• Patients should be instructed in deep breathing and coughing; this reopens the alveoli and helps to clear secretions from the lower respiratory.