Serotonin syndrome: a serious reaction to excess serotonin

When medications that increase serotonin levels in the brain are used, there is a possibility of an adverse reaction known as serotonin syndrome.

This condition is the result of an excessive accumulation of serotonin, a neurotransmitter involved in key functions such as mood, appetite, digestion, and sleep regulation.

While these treatments can be very effective, an inappropriate combination of substances can disrupt the chemical balance of the nervous system and trigger dangerous symptoms.

How is this reaction triggered?

The syndrome appears when the serotonergic system is overstimulated, which can happen when combining different medications that act on this system or when abruptly increasing the dose of one of them.

This overload is not usually due to a single factor, but to the interaction of multiple elements. Drugs such as antidepressants, certain painkillers, medications to treat nausea, recreational drugs, and even supplements can have an influence if taken at the same time or without proper medical supervision.

Common examples of substances involved include:

• Medications that inhibit serotonin or norepinephrine reuptake

• Compounds used for anxiety or chronic pain

• Drugs that alter neurotransmitter levels, such as some hallucinogens

• Substances that block or stimulate serotonergic receptors

The risk increases when these substances are combined without proper monitoring, especially if their potential interaction is unknown.

Clinical manifestations

The symptoms of this condition usually appear within a few hours after ingesting the triggering drug or increasing the dose. They are grouped into three levels of severity:

Moderate symptoms:

• Mental agitation, nervousness, or confusion

• Rapid pulse and high blood pressure

• Tremors, muscle stiffness, or involuntary movements

• Intense sweating, nausea, diarrhea, or dizziness

Severe symptoms:

• Hyperthermia (very high fever)

• Uncontrolled heart rate

• Seizures

• Fainting or loss of consciousness

• Risk of damage to vital organs if action is not taken in time

Given how quickly this condition can develop, it is crucial to recognize the initial signs and disconti