How Do Tetracyclic Antidepressants Work?

Tetracyclic antidepressants are medications prescribed to treat depression and anxiety. Tetracyclic antidepressants are so named because of the four rings of atoms in their molecular structure, and are closely related to tricyclic antidepressants which have three rings.

Tetracyclic antidepressants relieve depression and anxiety by increasing the levels of serotonin and norepinephrine and regulating their activity. Serotonin and norepinephrine are chemicals (neurotransmitters) that nerve cells (neurons) release into the space (synapse) between them to communicate with each other.

Tetracyclic antidepressants increase the availability of serotonin and norepinephrine by preventing their reabsorption (reuptake), a natural process in the brain. Serotonin and norepinephrine play important roles in the regulation of sleep, digestion, cognition, mood and behavior, and increasing their levels help in relieving depression and anxiety.

Tetracyclic antidepressants are also thought to work by modulating the activity of serotonin and norepinephrine receptors, which are protein molecules on cell surfaces that initiate intracellular action when stimulated by these neurotransmitters.

Tetracyclic antidepressants are oral tablets, approved by the FDA for the treatment of depression and anxiety associated with depression.

Side effects of tetracyclic antidepressants may include the following:

Common

• Fatigue
• Sedation
• Lethargy
• Weakness
• Constipation
• Dry mouth
• Blurred vision

Less Common

• Agitation
• Anxiety
• Headache
• Insomnia
• Nausea
• Vomiting
• Sweating

Infrequent

• Orthostatic hypotension (blood pressure drop when standing up from sitting or lying down)
• ECG changes
• Tachycardia (rapid heartbeat)
• Confusion
• Extrapyramidal symptoms (drug-induced movement disorders)
• Dizziness
• Paresthesia (prickling sensation)
• Tinnitus (ringing in the ears)
• Rash
• Elevated liver enzymes
• Sexual dysfunction

Rare

• Seizure
• Agranulocytosis (low granulocytes, immune cells with granules)
• Leukopenia (low levels of leukocytes, a type of immune cell)
• Thrombocytopenia (decrease in platelet count)
• Eosinophilia (high count of eosinophils, a type of white cells that are elevated in infections or allergies)
• Syndrome of inappropriate antidiuretic hormone secretion (SIADH, a disorder which causes water retention)

Information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

The generic name of the tetracyclic antidepressant drug used to treat depression is:

• maprotiline