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Tricyclic Drug

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SSRI, Citalopram, Paroxetine

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Researchers discovered the first antidepressants purely by chance in the 1950s.  Seeking a treatment for schizophrenia, scientists at the Munsterlingen asylum in Switzerland found that a which drug manipulated the balance neurotransmitters — the chemicals that control mood, pain and other sensations — sent patients into bouts of euphoria.  For schizophrenics, of course, that only made their condition worse.  But researchers soon realized it made their discovery perfect for patients with depression. On first trying it in 1955, some patients found they were newly sociable and energetic and had quickly referred to the drug as a "miracle cure." The drug, called imipramine was marketed as Tofranil in 1958, and was rapidly followed by many rival drug companies. They are known as tricyclics, named for their three-ring chemical structure.  Now antidepressants are one of the most popular forms of medication on the market today with approximately 1 in 10 Americans filling prescriptions.

Antidepressants are in a category of psychotropic drugs, which simply mean drugs that alter chemical levels within the brain resulting in a change of mood and behavior.

There Are Three Classes of Antidepressants;

Tricyclics or Heterocyclics

This form of antidepressant is usually prescribed when the other more popular SSRi’s are unsuccessful.  Tricyclics are commonly prescribed to sufferers of migraines and chronic pain.  This is an older form of an antidepressant with more severe side effects, and they carry a higher risk of overdose as well.  Newer medications are much safer.  Tricyclics can also have fatal results if mixed with alcohol.  These drugs are a reuptake inhibitor which means they block the absorption of serotonin and norepinephrine back into the neuron, meaning they remain longer in the synapse; the gap between two neurons.


This class of drug has proven to have greater side effects and are not widely used in comparison to SSRIs.  These drugs work by blocking an enzyme that deactivates neurotransmitters, resulting in an increase in serotonin.  MAOI’s can be taken in pill or patch format.  However, MAOI’s are known to carry a risk of certain dangerous drug interactions, and are highly dangerous when taken with SSRIs or any other drug that manipulates serotonin levels.  In fact, doctors recommend not taking SSRIs within 5 weeks of taking fluoxetine (Prozac) due to Prozac’s long ½ life.

MAOIs have been known to increase blood pressure when mixed with certain foods such as aged cheeses, sauerkraut, chicken livers, dried meats and fish, figs, red wine and concentrated yeast products, and can result in dangerous side effects.

This class of drugs have been successful in helping eating disorders and agoraphobia. 

SSRI’s (Selective Serotonin Reuptake Inhibitors)

Probably the most popular choice of antidepressants, SSRIs actively blocks the reuptake of serotonin, leaving the neurotransmitter available longer within the synapse, (gap between the two neurons) and resulting in greater moods and emotion.  Due to the nature of the drug and its relationship with serotonin; SSRIs have a lower side effect probability.  These SSRIs have also been effective in treatment of anxiety and obsessive compulsive disorder.

Serotonin Syndrome is a condition that can occur if other serotonin altering drugs are used simultaneously. 


Symptoms of serotonin syndrome are:

  • Confusion
  • Agitation
  • Profuse sweating
  • Tremors
  • Myoclonic body jerks
  • Fever
  • Diarrhea

However, SSRi’s can be combined with other antidepressants with a different mechanism of action other than serotonin altering.

SNRi’s (Selective Serotonin and Norepinephrine Reuptake Inhibitors)

This dual inhibitor is a class of drug that tends to be effective for symptoms of fatigue and lack of motivation.  Combined with SSRi’s, they have been shown to be quite effective.

Aminoketone Class

This is a stimulant classified as a norepinephrine and dopamine reuptake inhibitor. The aminoketones will block the transporting of the neurotransmitters ‘norepinephrine and dopamine’.  These transporters would otherwise cause an uptake of norepinephrine and dopamine, in other words the neurotransmitters will be absorbed back into the neuron.

They will block the uptake, and the norepinephrine and dopamine remain in the synapse longer. They have very few side effects and are not known to cause fatigue or weight gain.  In fact, sexual dysfunction and loss of libido have been treated with Wellbutrin to reverse the sexual side effects of some SSRI’s.  Another use for Wellbutrin is for the cessation of smoking, which has proven to be very successful. 

A Few More Commonly Known Brands:

  • Celexa - SSRIs
  • Cymbalta - SNRIs
  • Effexor - SNRIs
  • Paxil - SSRIs
  • Prozac - SSRIs
  • Wellbutrin - Aminoketones
  • Zoloft – SSRIs

As you can see, the SSRIs are significantly more popular than the other drug classes.

 What Exactly Does ½ Life Mean?

The full dose of a specific drug is within the pill that one has taken.  The ½ life is the amount of time for exactly ½ the original dose to be used up or to have lost half  its pharmacologic activity. 


Withdrawal occurs by a process called ‘down regulation’.  The brain will acknowledge the altering of chemicals and it will accommodate for this by decreasing its own natural release.  This process can take up to a month until the brain finds a comfortable chemical balance with the use of a new drug.  Once this happens then the medication can work very well.  Withdrawal does not necessarily occur with patients that have been on antidepressants for less than a month, and that can be explained by the timeline of brain chemical adjustments.

Typical onset of withdrawal can range from 1 - 2 days (Effexor) to 2 – 3 weeks (Prozac), depending on the ½ life.  Research shows a higher possibility of withdrawal symptoms in drugs with a shorter ½ life, as with Effexor for example.

Withdrawal symptoms:

** Sudden stopping of antidepressants can be very dangerous.

 Tricyclics / Heterocyclics

  • Drop in blood pressure
  • Dizziness
  • Fatigue
  • Dry mouth
  • Constipation
  • Blurred vision
  • Sexual dysfunction
  • Weight gain
  • Difficulty urinating


  • Drop in blood pressure
  • Dizziness
  • Fatigue
  • Insomnia
  • Sexual dysfunction
  • High blood pressure
  • MAOIs can cause birth defects and should not be taken by pregnant women.


  • Dizziness
  • Fatigue
  • Dry mouth
  • Nausea
  • Agitation
  • Lethargy / Lack of motivation
  • Headache and flu-like symptoms
  • Heart palpitations and chest pain
  • Weight gain
  • Depression
  • Sexual side effects
  • Electric type shock sensations in the brain
  • Convulsions


  • Dizziness
  • Fatigue
  • Dry mouth.
  • Sweating
  • Insomnia
  • Anxiety or agitation.
  • Constipation

Things to Know

  1. Depression is not a character flaw; it is a chemical imbalance that requires treatment with antidepressants.
  2. Prescriptions can sometimes be on a trial and error basis, one brand may not work, while another one may.
  3. Sometimes one type of antidepressant may need to be complimented with another type.
  4. Cognitive Behavioral therapy is often recommended with antidepressant treatment.

Why are Antidepressants Needed?

Antidepressants, as we now know, work very well for depression, and it is this condition that can place an extreme weight onto those that suffer.  Depression isn’t solely about feeling sad, it is also about the feeling of complete depletion of energy, and it can hinder one’s social life, as those with depression are more inclined to remain at home.  Relationships become strained, and work balance and relationships can end up becoming compromised.  It is for these reasons that antidepressants can be so beneficial to those that suffer.  It is important to remember that depressive symptoms come from a chemical imbalance, and it is something that should not be stigmatized.   Antidepressants, when taken under the supervision of a physician can truly be a miracle drug for those that suffer.


  6. Glenmullen, Joseph MD, The Antidepressant Solution – A Step by Step Guide to           Safely Overcoming Antidepressant Withdrawal, Dependence and “Addiction”         (2005) Free Press, NY
  7. Stringer, Janet L., Basic Concepts In Pharmacology – A Student’s Survival Guide (2006) McGraw Hill Companies Inc.
  8. Diamond, Ronald J. Instant Psychopharmacology Third Edition (2009) W.W. Norton and Company, NY


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