Lesson Concept.

Introduction To CNS Pharmacology

CNS Stimulants

Antidepressants

Hypnotics and Anxiolytics

Antiparkinsons

Antischizophrenics

Antiepileptics

Dyspepsia and Peptic Ulcer Disease

Cathartics and Purgatives

Antiemetics

Drugs Affecting The Endocrine System

Antithyroids

Parathyroid Disorders

Gonadal Disorders

Pituitary Disorders

Pancreatic Disorders

Drug Therapy For Bones and Joints

Skeletal Muscle Relaxants

Osteoarthritic Drugs

Rheumatoid Arthritic Drugs

Drugs For Gouty Arthritis

Drugs For Osteoporosis

Analgesics

Antipyretics

Anti-inflammatory Drugs

ANTIDEPRESSANTS #5

The second group of the commonly used antidepressant is Serotonin/Norepinephrine Reuptake Inhibitors (SNRIs).

MOA: SNRIs bind to pre-synaptic nerve endings and prevent the reuptake of both serotonin and norepinephrine, resulting in greater concentrations of both neurotransmitters in the synaptic clefts to increase neuronal activities.

ADR:

• Nausea & Vomiting
• Insomnia
• Dizziness
• Sedation
• Constipation
• Increase in blood pressure (at high doses)
• Sexual dysfunction

EX:

• Venlafaxine hydrochloride (Efexor XR*)
• Duloxetine                            (Symbalta*)

TU:

• Depression                                                                             (Venlafaxine & Duloxetine)
• Anxiety                                                                                   (Venlafaxine)
• Socialized anxiety disorder                                                    (Venlafaxine)
• Panic disorder                                                                         (Venlafaxine)
• Diabetic neuropathy                                                               (Duloxetine)
• Moderate to severe stress urinary incontinence in women (Duloxetine)

SP:

• Pregnancy & lactation
• Avoid sudden withdrawal
• Moderate to severe renal or hepatic impairment
• History of myocardial infarction
• Close blood pressure and cholestrol serum monitoring

ANTIDEPRESSANTS #4

In this post, we would be looking further into the selective serotonin reuptake inhibitors (SSRIs) group.

MOA: SSRIs bind to the pre-synaptic nerve ending and block the reuptake of serotonin. Increasing level of serotonin in the synaptic cleft enhance neuronal activities via continuous binding of that particular neurotransmitters to post-synaptic receptors.

ADR:

• Insomnia
• Nausea
• Male sexual dysfunction
• Suicidal approaches, especially in teenagers
• Headaches
• Weight loss
• Anticholinergic effects such as dry mouth and blurry vision
• Withdrawal symptoms such as tremors and anxieties

EX:

• Citalopram            (Cipram*)
• Fluoxetine             (Prozac*) 
• Fluvoxamine          (Luvox*)
• Paroxetine              (Paxil*)
• Sertraline                (Zoloft*)

TU:

• Depression                                 (Flouxetine)
• Obsessive compulsive disorder (Fluvoxamine)
• Panic disorder
• Anxiety

SP:

• Cardiac disease
• Diabetics
• Patients with unstable epilepsy
• Hepatic and renal impairment

Antidepressants #3

Currently, there are four treatment options for treating depression. They are:

1. Pharmacotherapy, by the usage of medications known as mood enhancers or antidepressants
2. Psychotherapy
3. Electroconvulsive therapy
4. Non-pharmacological treatment

For now, I am going to focus on non-pharmacological treatments. They include,

• Psychoeducation about depression and treatment options available
• Stress reduction techniques
• Balanced nutrition
• Regular exercise

For pharmacotherapeutic treatments, they include the usage of antidepressants. There are four major classes of antidepressants.

• Selective Serotonin Reuptake Inhibitors (SSRIs)
• Serotonin/Norepinephrine Reuptake Inhibitors (SNRIs)
• Monoamine Oxidase Inhibitors (MAOi)
• Tricyclic Antidepressants (TCAs)

These antidepressants' classes would be discussed further in the next post.

Antidepressants #2

Depression could be caused by two factors, either by situations or biological.

Situational Causes of Depression.

• Unpleasant life circumstances
• Negative thinking patterns
• Substance abuse (such as drugs)

Unpleasant situations may cause depression.

Biological Causes of Depression.

• Genetics
• Hormonal imbalances
• Neurobiological dysfunction
• Symptoms from second disorder (such as head trauma or cancer)

Genetics can cause depression as well.

In the next post, we will look further into such treatment options available for depressive patients.

Antidepressants #1

Have you ever wondered what depression is? In simple words, depression is a type of mood disorder. In order to understand depression, we should first look into the definition of mood disorders.

Mood disorders are elevated or depressed moods over a period of time that affects the ability of a person to function well. There are two common types of mood disorders, mainly:

• Major depression
• Bipolar disorder (manic depression or mania)

On the other hand, depression is a disorder characterized by few common symptoms, such as:

• Depressed mood
• Lack of energy
• Sleep disturbances
• Abnormal eating patterns
• Feeling of guilt, despair and misery
• Inability to concentrate or making decisions
• GI pain, joint pains or headaches
• Obsession with death
• Avoid being around with other people
• Lack of interest in personal appearance or sex
• Hallucinations
• Delusions

Pathophysiologic explanation on depression involves three main neurotransmitters; norepinephrine, dopamine and serotonin. This explanation is divided to two hypothesis, the monoamine hypothesis and the permissive hypothesis.

Monoamine hypothesis.

In monoamine hypothesis, depression is caused by decreased concentrations of both norepinephrine and dopamine, alongside serotonin in the central nervous system.

Permissive hypothesis.

Permissive hypothesis explains that a decrease in both serotonin and norepinephrine precipitates depression. On the other hand, decreasing serotonin and increasing norepinephrine causes mania (bipolar disorder).

In the next post, I would go on further into causes of depression.

Hypnotics and Anxiolytics: Part 7.

Hydroxyzine is a another medication used in the treatment of anxiety disorders. It belongs to antihistamines group, and possess a distinct anti-emetics activity.

MOA: Hydroxyzine competes with histamine for histamine receptors (H-1), thus blocking the effects of histamine. It produces brochodilation and relaxation of skeletal muscles.

ADR:

• Drowsiness.
• CNS depression.
• Paradoxical CNS stimulation.
• Dry mouth.
• Constipation.
• Blurry vision.
• GI disturbances.
• Tachycardia.

TU:

• Mild to severe anxiety, particularly used in drug abusers due to low tendency of habituation.

PRCTN:

• Pregnant and lactating mothers.
• Porphyric patients.
• Renal and liver impairment.

The next drug would be Zolpidem, commonly used to treat both anxiety and insomniac patients.

MOA: Zolpidem acts on the subdivision of benzodiazepines receptors in CNS. It produces hypnotic effects, accompanied by strong sedation. However, the duration of action is short.

ADR:

• Nightmares.
• Agitation.
• Headache.
• GI upset.
• Dizziness.
• Daytime drowsiness.
• Euphoria.
• Vertigo.
• Confusion.

TU:

• Treatment of mild anxiety and insomnia.

PRCTN:

• Pregnant and lactating mothers.
• Obstructive sleep apnea.
• Renal and hepatic impairment.
• Myasthenia gravis.

The last type of drug used in the treatment of anxiety disorder is Zaleplon. It is also a common medication given to patients with insomnia.

MOA: Interact with GABA sub-complex type A by binding selectively with benzodiazepine-1 receptor to produce sedative and hypnotic effects.

ADR:

• Dry mouth.
• Asthenia.
• Headaches.
• Light-headedness.
• Dizziness.
• Myalgia.
• Fever.
• Migraine. 

TU:

• Treatment of anxiety and insomniac disorders.

PRCTN:

• Pregnant and lactating mothers.
• Hypersensitivity.
• Severe hepatic impairment.

Less used medications for these anxiety disorders include chloral hydrate and ethanol. Chloral hydrate produces both sedative and hypnotic effects that lasts about 30 minutes. On the other hand, ethanol is not used today due to the toxic effects that can be percipitated.

MOA: Depress the CNS via its metabolite, trichloroethanol.

ADR:

• Gastric irritation.
• Vertigo.
• Ataxia.
• Ketonuria.
• Eosinophilia.

TU:

• Treatment of insomnia and mild anxiety.

PRCTN:

• Pregnant and lactating mothers.
• Cardiac disorder patients.
• Hepatic or renal impairment.
• Porphyric patients.
• Gastritis patients.

This marks the end of this topic. If you have any questions, feel free to ask in the comment form below and I'll get back to you as soon as I can.