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Melatonin - Side Effects, Precautions, and Contraindications

What side effects can Melatonin cause?

The mentioned side effects generally affect up to 10% of patients.

  • Nausea or vomiting
    • Take this medication with or after food
    • Take simple meals and avoid rich or spicy foods
  • Light-headedness (especially during a sudden change in posture)
    • Get up slowly from a sitting or lying down position
  • Feeling tired or drowsy
    • Avoid driving or engaging in activities requiring concentration
  • Feeling clumsy or unsteady
    • Speak to your doctor if it becomes bothersome
  • Headache
    • Speak to your doctor if it becomes bothersome

Most of the side effects listed here will improve with time. Speak to your doctor if they continue, get worse or are affecting your daily life.

Rarely this medication may cause:

  • Fever
  • Severe chest pain
  • Irregular heartbeat
  • Memory loss (amnesia)
  • Abnormal thinking or changes in behaviour
  • Unusual excitement, nervousness, irritability, or agitation
  • Blurred vision
  • Fainting episodes
  • Seizures (fits)
The symptoms of a drug allergy include one or more of the following:
  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

If you experience any of these side effects, you should stop your medication and inform your healthcare professional immediately.

Please also take note that not all possible side effects are listed above. If you have any concerns about your medication, please consult your doctor or pharmacist.

Before taking Melatonin , what precautions must I follow?

Inform your healthcare professional if:

  • You are allergic to this medication or any of the other ingredients of this medication
  • You are pregnant, planning to become pregnant, or breastfeeding. If you are pregnant and/or breastfeeding, your doctor would have discussed the potential benefits and side-effects with you. If you have further questions or concerns, do consult your doctor.
  • You are taking any other medications including over-the-counter medications, supplements, traditional Chinese medicine and herbal remedies. Some of them may affect how this medication works or cause serious drug interactions.
  • You are smoking. Smoking may decrease the amount of Melatonin that stays in your body.
  • You have or have ever had:
    • Other drug allergies or lactose intolerance (congenital galactosaemia, glucose malabsorption syndrome or lactase deficiency)
    • Medical conditions such as:
      • Lung, liver or kidney disease
      • Drug or alcohol abuse
      • Sleep apnea (temporary stopping of breathing during sleep) or
      • Any autoimmune disease (where the body is ‘attacked’ by its own immune system)

What food or medicine must I avoid when I take Melatonin ?

Avoid drinking alcohol while taking this medication as it can reduce the effect of this medication on sleep.

Melatonin - Additional Information

  • Updated on 10/31/2021 12:00:00 AM
  • Article contributed by PSS National Medication Information Workgroup PSS National Medication Information Workgroup
The information provided is not intended as medical advice. Terms of use. Information provided by SingHealth

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