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Anti depressants- Parmacolgy

Date post:07-Aug-2015
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  1. 1. By- Dr.Namrata Mohan Msc. Final Year
  2. 2. Depression varies from person to person, but there are some common signs and symptoms. Its important to remember that these symptoms can be part of lifes normal lows. But the more symptoms you have, the stronger they are, and the longer theyve lasted the more likely it is that youre dealing with depression.
  3. 3. SHALL WE PLAY!! A. I feel sad most of the time, it is persistent, so much that I am always in a low mood YES NO B. I cannot seem to enjoy my hobbies and various interests YES NO C. I experience low energy, Im tired most of the times and lack the will to take up new things YES NO D. I feel such low most of the times, whole day and most part of the week YES NO E. I dont remember when was last time I had a great sleep, and woke up refreshed YES NO F. I cant seem to concentrate on anything and I really cant take my own decisions YES NO G. I dont think I can be called a self- confident personality YES NO H. I am afraid I might kill myself someday YES NO I. I find myself guilty for most of the things that go wrong YES NO
  4. 4. DIAGNOSTIC CRITERIA FOR DEPRESSION ICD-10 uses an agreed list of ten depressive symptoms Key symptoms: persistent sadness or low mood and / or loss of interests or pleasure fatigue or low energy at least one of these, most days, most of the time for at least 2 weeks if any of above present, ask about associated symptoms: disturbed sleep poor concentration or indecisiveness low self-confidence poor or increased appetite suicidal thoughts or acts agitation or slowing of movements guilt or self-blame the 10 symptoms then define the degree of depression and management is based on the particular degree not depressed (fewer than four symptoms) mild depression (four symptoms) moderate depression (five to six symptoms) severe depression (seven or more symptoms, with or without psychotic symptoms) symptoms should be present for a month or more and every symptom should be present for most of every day
  5. 5. CAUSES 0F DEPRESSION Like most of the Mental conditions, exact cause for depression is not known, but it is believed to be triggered by : Biological differences Brain Chemistry Traumatic events Family History
  6. 6. Major depression Major depression is characterized by the inability to enjoy life and experience pleasure. The symptoms are constant, ranging from moderate to severe. Left untreated, major depression typically lasts for about six months. Some people experience just a single depressive episode in their lifetime, but more commonly, major depression is a recurring disorder. Dysthymia (recurrent, mild depression) Dysthmia is a type of chronic low-grade depression. More days than not, you feel mildly or moderately depressed, although you may have brief periods of normal mood. The symptoms of dysthymia are not as strong as the symptoms of major depression, but they last a long time (at least two years). Some people also experience major depressive episodes on top of dysthymia, a condition known as double depression
  7. 7. also known as manic depression, is characterized by cycling mood changes. Episodes of depression alternate with manic episodes, which can include impulsive behavior, hyperactivity, rapid speech, and little to no sleep. Typically, the switch from one mood extreme to the other is gradual, with each manic or depressive episode lasting for at least several weeks. When depressed, a person with bipolar disorder exhibits the usual symptoms of major depression. However, the treatments for bipolar depression are very different. In fact, antidepressants can make bipolar depression worse. Bipolar Disorder: When Depression is Just One Side of the Coin
  8. 8. DEPRESSION & SUICIDE Depression is a major risk factor for suicide. 15% of people with such disorders show suicidal behaviours in their lifetime. Thoughts of death or suicide are a serious symptom of depression, so take any suicidal talk or behaviour seriously. It's not just a warning sign that the person is thinking about suicide: it's a cry for help!!
  10. 10. WHAT ARE ANTI-DEPRESSANTS Antidepressants are drugs used for the treatment of major depressive disorder and other conditions, including dysthymia, anxiety disorders, obsessive compulsive disorder, eating disorders, chronic pain, neuropathic pain and, in some cases, dysmenorrhoea, snoring, migraines, attention- deficit hyperactivity disorder (ADHD), substance abuse and sleep disorders. They can be used alone or in combination with other medications.
  11. 11. CLASSES OF ANTI-DEPRESSANTS The most important classes are: SEROTONIN NOREPINEPHRINE REUPTAKE INHIBITORS (SSRIs & SNRIs) TRICYCLIC ANTIDEPRESSANTS (TCAs) MONOAMINE OXIDASE INHIBITORS (MAOIs) Other drugs include- buprenorphine, low dose antipsychotics, St.John Worts
  12. 12. CLASS : MAO INHIBITORS MAO (Monoamine oxidase) is a Mitochondrial enzyme involved in the oxidative de-amination of biogenic amines (Adr, NA, DA, 5-HT). MAO is found bound to the outer membrane of most of the cell types of body. In humans there are two subtypes- MAO A & MAO-B Both are found in CNS (neurons & astroglia) - outside CNS: MAO-A : liver, pulmonary vascular endothelial, GI tract and place
  13. 13. SIGNIFICANCE OF MAO MAO-A is, for which they display different specificities. Serotonin, melatonin, noradrenaline, and adrenaline are mainly broken down by MAO-A. Phenethylamine and benzylamine are mainly broken down by MAO-B. Both forms break down dopamine, tyramine, and tryptamine equally.
  14. 14. PHARMACOLOGY Because of the vital role that MAOs play in the inactivation of neurotransmitters, MAO dysfunction (too much or too little MAO activity) is thought to be responsible for a number of psychiatric and neurological disorders. For example, unusually high or low levels of MAOs in the body have been associated with schizophrenia, depression, attention deficit disorder, substance abuse, migraines and irregular sexual maturation . Monoamine oxidase inhibitors are one of the major classes of drug prescribed for the treatment of depression, although they are often last-line treatment due to risk of the drug's interaction with diet or other drugs. Excessive levels of catecholamines (epinephrine, norepinephrine, and dopamine) may lead to a hypertensive crisis, and excessive levels of serotonin may lead to serotonin syndrome. In fact, MAO-A inhibitors act as antidepressant and antianxiety agents, whereas MAO-B inhibitors are used alone or in combination to treat Alzheimers and Parkinsons diseases.
  15. 15. SPHERE OF ACTION CNS: MAO inhibitors elevate mood - Maximal inhibition occurs in 3-5 days - Mood elevating effect may take 3-4 weeks. - Markedly supress REM sleep in non- depressed. Corrective in depressed. CVS: Cause fall in BP - due to ganglionic interference - decreasing central sympathetic outflow etc.
  16. 16. PHARMACOKINETICS Well absorbed orally Hydrazine compounds generate some metabolites more potent and irreversible inhibitors of MAO ,inactivated by acetylation HIT & RUN Drugs- themselves stay in the bosy for relatively short periods but their effects continue for 2-3 weeks of discontinuation.
  17. 17. COMMON MAOs NON-SELECTIVE Hydrazines Phenelzine Isocarboxacid Non-Hydrazine Tranylcypromine ISOZYME SELECTIVE MOA-A Clorgiline Moclobemide MAO-B Selegiline (deprenyl)
  18. 18. INTERACTIONS & ADVERSE REACTIONS Combining MAO inhibitors with foods or drinks containing tyramine can result in dangerously high blood pressure, which can lead to a stroke or heart attack. Because of this danger, MAOIs are not typically chosen as a first-line depression treatment, there has to careful monitoring of diet, with restrictions which may include cheese, beers, chocolates & wine
  19. 19. COMMON SIDE EFFECTS : Dizziness Insomnia Weight gain Headaches Sexual problems Daytime sleepiness Risk of Heart attack Dry Mouth Nausea
  20. 20. SELECTIVE SEROTONIN REUPTAKE INHIBITORS ( SSRIs) Capable of affecting a specific neural site of action (eg, uptake pumps, receptors) while avoiding effects on other site of action The SSRIs (selective serotonin reuptake inhibitors) are the most commonly prescribed class of antidepressants. They act on a chemical in the brain called serotonin. The SSRIs are preferred over older classes of antidepressants such as tricyclic antidepressants and MAOIs because their adverse effects are less severe. The SSRIs can also cause serious withdrawal symptoms if stopped abruplty.
  21. 21. MECHANISM OF ACTION OF SSRIs All selective serotonin reuptake inhibitors have the same general mechanism of action. SSRIs seem to relieve symptoms of depression by blocking the reabsorption (reuptake) of serotonin by certain nerve cells in the brain. This leaves more serotonin available, which enhances neurotransmission and improves mood. SSRIs are called selective because they seem to affect serotonin significantly more than other neurotransmitters. Thus, the medications work by allowing the body to make the best use of the reduced amounts of serotonin that it has at the time. In due course, the levels of natural serotonin will rise again, and in some instances the SSRI can be reduced and withdrawn.
  22. 22. COMMON SSRI GENERIC NAMES Fluoxetine (Prozac) Fluvoxamine (Luvox) Sertraline (Zoloft) Paroxetine (Praxil) Escitalopram (Lexapro) Citalopram (Celexa)
  23. 23. COMMON SIDE EFFECTS Nausea Insomnia Dizziness Weight gain or loss Tremors Sweating Anxiety and restlessness Decreased sex drive Drowsiness or fatigue Dry mouth Diarrhea or constipation Headaches
  24. 24. TRICYCLIC ANTIDEPRESSANTS Imipramine (a diabenzapine- analogue of phenothiazine in which sulphur atom of the central ring has bee
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