[PCOL-FIN-02-PT3] ANTIDEPRESSANTS

THIS FLASHCARDS IS ABOUT [PCOL] DRUGS OF ANTIDEPRESSANTS.

MAOIs

This inhibits the enzyme monoamine oxidase (MAO) and the last choice for drugs.

Monoamine oxidase

This degrades monoamine neurotransmitters.

MAO_A

This MAO is responsible for the metabolism of serotonin (5-HT), norepinephrine, tyramine, and histamine.

• Serotonin

• Norepinephrine

• Tyramine

• Histamine

MAO_A is responsible for the metabolism of?

Hint: SN-TH

MAO_B

This MAO is responsible for the metabolism of dopamine only.

Dopamine

MAO_B is responsible for the metabolism of?

MAO_A

Between the two subtypes of MAO, which is the only related to the management of depression?

1. Monoamine oxidase (MAO)

2. Monoamines

MOA of MAOIs:

Inhibits the enzyme (1)________, preventing metabolism of (2)_____.

• Phenelzine

• Isocarboxazid

• Tranylcypromine

What are the (3) Examples of Non-Selecting MAO-is?

Hint: Phe-Iso-Tran

Moclobemide

What is an example of selective MAO_A?

Info

Selective MAO_A increases the level of norepinephrine and serotonin.

Selegiline

What is an example of selective MAO_B?

Info

Selective MAO_B increases the level of dopamine and it is not recommended for depression but is good for the symptoms of Parkinson’s Disorder.

• Drug-Drug interactions

• Drug-Food interactions

What are the (2) Adverse Effects of MAOIs?

Norepinephrine

MAOIs increases the level of what neurotransmitter?

Info

If tyramine (source for tyrosine) is found in our body, the level of norepinephrine increases (cheese, juice, cheddar).

Tyrosine

Tyramine is a source for?

Monoamine oxidase (MAO)

Which enzyme is responsible in degrading tyramine?

Info

If MAO is inhibited, the level of tyramine increases thus producing more norepinephrine. If the tyramine from our stomach reach the pre-synapse or axons, it will facilitate the synthesis of norepinephrine enhancing the level of norepinephrine in our body.

Info

Norepinephrine binds to a₁ and B₁ receptors (enhanced activity; double effect). As a result, it will cause hypertensive crisis or worse, cerebral stroke.

1. Hypertensive crisis

2. Cerebral stroke

As a result of norepinephrine increase level (double effect), it will cause (1)____ crisis or worse, (2)____ stroke.

Bupropion

This atypical antidepressants (MOA) inhibits the reuptake (transporter) of NE and DA (equally).

Smoking cessation

Bupropion is used for?

Schizophrenia

Bupropion is contraindicated to psychosis especially?

Mirtazapine

This atypical antidepressants (MOA) inhibits presynaptic a₂ receptors (autoregulation; enhance the release of NE); selectively blocks 5-HT receptors in the post-synapse blocks histamine receptors.

• Trazadone

• Nefazodone

These (2) atypical antidepressants (MOA) inhibits the reuptake of 5-HT (blocks SERT); blocks post-synaptic 5-HT₂ receptors; antagonize H₁-receptor (highly sedating).

Nefazodone

This atypical antidepressant was withdrawn from the market because of its hepatotoxic property.