Review: could Promethazine cause Serotonin Syndrome?


Serotonin syndrome is found among people who take Promethazine, especially for people who are female, 50-59 old , have been taking the drug for < 1 month, also take medication Citalopram, and have Nausea . We study 6,746 people who have side effects while taking Promethazine from FDA and social media. Among them, 37 have Serotonin syndrome. Find out below who they are, when they have Serotonin syndrome and more.

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Promethazine has active ingredients of promethazine hydrochloride. It is often used in nausea. (latest outcomes from Promethazine 7,916 users)

Serotonin Syndrome

Serotonin syndrome (occurs when two drugs that affect the body's level of serotonin are taken together at the same time) has been reported by people with depression, pain, stress and anxiety, major depression, insomnia (latest reports from 9,742 Serotonin syndrome patients).

On Oct, 22, 2016

6,746 people reported to have side effects when taking Promethazine.
Among them, 37 people (0.55%) have Serotonin Syndrome

Number of reports submitted per year:

Could Promethazine cause Serotonin syndrome?

Time on Promethazine when people have Serotonin Syndrome *:

  • < 1 month: 100 %
  • 1 - 6 months: 0.0 %
  • 6 - 12 months: 0.0 %
  • 1 - 2 years: 0.0 %
  • 2 - 5 years: 0.0 %
  • 5 - 10 years: 0.0 %
  • 10+ years: 0.0 %

Gender of people who have Serotonin Syndrome when taking Promethazine *:

  • female: 94.12 %
  • male: 5.88 %

Age of people who have Serotonin Syndrome when taking Promethazine *:

  • 0-1: 0.0 %
  • 2-9: 8.82 %
  • 10-19: 0.0 %
  • 20-29: 0.0 %
  • 30-39: 2.94 %
  • 40-49: 29.41 %
  • 50-59: 47.06 %
  • 60+: 11.76 %

Top conditions involved for these people *:

  • Nausea (10 people, 27.03%)
  • Pain (9 people, 24.32%)
  • Procedural Pain (7 people, 18.92%)
  • Post Herpetic Neuralgia (6 people, 16.22%)
  • Antidepressant Therapy (6 people, 16.22%)

Top co-used drugs for these people *:

  • Metformin (15 people, 40.54%)
  • Citalopram (15 people, 40.54%)
  • Ondansetron (12 people, 32.43%)
  • Morphine (12 people, 32.43%)
  • Metoclopramide (9 people, 24.32%)

Top other side effects for these people *:

  • Drug Interaction (9 people, 24.32%)
  • Pain (7 people, 18.92%)
  • Clonus (7 people, 18.92%)
  • Weight Decreased (6 people, 16.22%)
  • Agitation (6 people, 16.22%)

* Approximation only. Some reports may have incomplete information.

** Reports from social media are used.

How to use the study: print a copy of the study and bring it to your health teams to ensure drug risks and benefits are fully discussed and understood.

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