Causes of Serotonin Syndrome
Serotonin is a neurotransmitter. It is a type of chemical that transfers nerve signals. It is produced in the brain and spinal cord. The chemical helps in regulating the attention, the behaviour and the body temperature. It is also present in the intestine. Serotonin present in other vital organs regulates metabolic processes such as breathing, digestion and blood flow.
Serotonin syndrome is commonly caused when a combination of drugs are administered. For example when an antidepressant is given along with migraine medication it usually leads to serotonin syndrome.
A number of over-the-counter drugs, illicit drugs and dietary supplements also lead to serotonin syndrome. However the effects are not confined to these drugs alone.
List of Drugs that Cause Serotonin Syndrome
Serotonin Reuptake Inhibitors (SSRIs): SSRIs are the latest generation of antidepressants. These are called atypical antidepressants because their mechanism of action varies from traditional antidepressants. These include citalopram (Celexa), fluoxetine (Prozac, Sarafem), fluvoxamine, paroxetine (Paxil) and sertraline (Zoloft).
Serotonin and Norepinephrine Reuptake Inhibitors (SNRIs): These drugs act on two neurotransmitters at the same time. These include trazodone and venlafaxine (Effexor).
Bupropion: It is basically a tobacco-addiction medication (Wellbutrin, Zyban). It is also used as an antidepressant.
Monoamine Oxidase Inhibitors (MAOIs): These antidepressants act on the enzyme monoamine oxidase. These include isocarboxazid (Marplan) and phenelzine (Nardil).
Anti-migraine medication: Typical anti-migraine medications include almotriptan (Axert), naratriptan (Amerge), sumatriptan (Imitrex) and zolmitriptan (Zomig)
Lithium: Commonly used in bipolar disorder as a mood stabilizer (Eskalith, Lithobid).
Illicit drugs: These include LSD, Ecstasy, cocaine and amphetamines.
Herbal Supplements: These include St. John’s wort and ginseng.
Over-the-counter cough and cold medications: These include drugs such as dextromethorphan (Robitussin DM, Sudal DM).
Apart form this, anti-nausea drugs, antibiotics such as Linezolid (Zyvox) and retroviral drugs cause serotonin syndrome.