Brief Answer:
Through neurotransmitters and the psychological component

Detailed Answer:
Hi and thanks for the query,

Information is transmitted in the brain with the aid of substances called neurotransmitters. An increase in the frequency of discharge or a decrease leads to either excessive excitation (reaction) nor reduced excitation.

There are neurotransmitters in the brain that either excite specific reactions (excitatory neurotransmitters) or inhibit them (inhibitory neurotransmitters). Tricyclic anti depressants have a particular core structure, and inhibit release of specific neurotransmitters. Inhibition of these neurotransmitters involved in causing depression by these tricyclic anti depressants reduce the depressive action, thus helping in curing or alleviating depression.

Substances that do cause pain in some cases are similar to those that cause depression. Using tri cyclic anti depressants in some cases therefore do relieve pain.

Pain also has a psychological component, and reducing depression helps alleviate the pain.

Thanks and hope this helps. In case you need specific details, do not hesitate asking follow up questions through this medium. Thanks again and regards.

Bain LE, MD

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