Mirtazapine

What is Mirtazapine?

  • Mirtazapine is commonly used to treat mental health conditions such as depression, obsessive-compulsive disorder (OCD), and anxiety.

How Does it Work and Why is it Important to Take?

  • Mirtazapine works by increasing the levels of serotonin and noradrenaline in the brain, which can influence your mood.

  • Taking Mirtazapine is important for fostering a positive mental state and overall well-being.

The Dose of The Medication

  • The usual starting dose of Mirtazapine is 15mg to 30mg per day, with a maximum daily dose of 45mg.

  • In some cases, clinicians may recommend splitting the dose to take it twice a day.

How and When to Take It

  • Mirtazapine is typically taken once a day, usually at bedtime as it can cause drowsiness.

  • If prescribed twice a day, take the smaller dose in the morning and the higher dose at bedtime.

What to Expect

  • Immediate effects may not be noticeable; it takes patience.

  • Improvement may take a week, with full effects in 4-6 weeks.

What to Do if You Miss a Dose

  • If you miss a dose of once-daily Mirtazapine, skip it and take the next dose at your usual time—never double up.

  • For twice-daily dosing, adjust as follows:

    • Missed morning dose: Take it at bedtime with the evening dose.

    • Missed evening dose: Skip it, and resume normal dosing the next day.

Possible Side Effects

  • Increased appetite and weight gain

  • Nausea and vomiting

  • Headaches

  • Dry mouth

  • Feeling sleepy

  • Diarrhoea

  • Constipation

Management of Side Effects

  • Click here for common side effects and how to manage them.

  • Mirtazapine can increase hunger, so focus on healthy eating and exercise.

  • Some side effects improve as your body adjusts.

  • If severe, persistent or bothersome side effects occur, consult your GP, local pharmacy, or NHS 111.

Common Interactions

  • Inform your clinician about all medications, including over-the-counter and herbal supplements.

  • Avoid St. John’s Wort, a herbal remedy for depression.

Special Warnings

  • Seek immediate medical attention if your mood worsens or in emergencies.

  • Limit alcohol consumption to avoid increased drowsiness.

  • Do not abruptly stop treatment to avoid withdrawal symptoms.

Monitoring Your Progress

  • Regular check-ups with your GP clinician are important to monitor your response to the medication and assess potential side effects.

Where to Find More Information and Who to Contact

  • Refer to the patient information leaflet and the NHS website for more details.

  • If you have questions or experience unusual symptoms, contact your GP clinician, local pharmacy, or NHS 111.