Medically reviewed by Jessica Swirble, PharmD
Last updated on April 18, 2025
Drug Information | Side Effects | Use & Dosage | Request an Online Prescription
Mirtazapine is a prescription medication used to treat depression (also known as major depressive disorder).
Mirtazapine is prescribed to treat depression (major depressive disorder) in adults.
It is commonly prescribed in conjunction with other forms of treatment like psychotherapy (“talk therapy”).
Mirtazapine is classified as an atypical antidepressant. It works by increasing levels of serotonin and norepinephrine in the brain. Serotonin and norepinephrine are neurotransmitters that help regulate mood.
Mirtazapine is available as an oral tablet and an orally disintegrating tablet.
The dosage and frequency of use depend on the condition being treated, its severity, and how you respond to the medication.
Follow your healthcare provider's instructions regarding dosage and schedule. Do not exceed the prescribed dose or frequency of use without consulting your provider.
Mirtazapine is used to manage depression. The effects can be noticeable within a few weeks, but it may take up to four to six weeks for the full therapeutic effect to occur.
Continue using mirtazapine as prescribed, even if you start feeling better. Regular use according to your prescription is crucial for the management of your condition.
While mirtazapine is primarily used for treating depression, healthcare providers may prescribe it off-label for other conditions such as anxiety, insomnia, or post-traumatic stress disorder (PTSD).
Discuss any alternative uses of mirtazapine with your healthcare provider.
Mirtazapine is available in the following dosage forms:
Mirtazapine is a prescription medication. You must have a valid prescription from a licensed healthcare provider to obtain it.
The use of mirtazapine can lead to various side effects in some individuals.
Common mild side effects of mirtazapine use include:
More severe side effects include:
If you experience any severe or concerning side effects while taking mirtazapine, contact your healthcare provider right away.
Inform your healthcare provider about any existing medical conditions, allergies, or other medications you are taking before starting treatment with mirtazapine. This includes prescription drugs, over-the-counter medications, and dietary supplements, as they may interact with mirtazapine.
Tell your provider if you are taking these medications or supplements:
You should also mention medical conditions such as:
If you are pregnant, planning to become pregnant, or breastfeeding, discuss the potential risks and benefits of using mirtazapine with your healthcare provider.
Take mirtazapine exactly as prescribed by your healthcare provider. Do not exceed the recommended dose or duration of treatment.
Your provider may direct you to avoid alcohol while taking mirtazapine, as it can increase the risk of side effects.
Mirtazapine can cause drowsiness. Do not drive or operate machinery until you know how this medication affects you.
Complete the full course of treatment, even if you feel better, to ensure the medication's effectiveness in managing your symptoms.
In case of a mirtazapine overdose, seek medical attention immediately. Symptoms of overdose may include severe drowsiness, confusion, rapid heartbeat, or fainting. If you suspect an overdose, contact the poison control helpline at 1-800-222-1222 or call emergency services.
Mirtazapine is available in the following forms:
The typical starting dose of mirtazapine varies depending on the condition being treated, the severity of symptoms, and individual patient factors. It is crucial to follow your healthcare provider's instructions regarding dosage and administration.
For depression:
The dosage may be adjusted based on the response and tolerance to the medication. Your healthcare provider will determine the most appropriate dose based on your medical history and your response to the medication.
Mirtazapine should be taken as prescribed by your healthcare provider. Do not exceed the recommended dose or duration of treatment without consulting your provider.
If you have any questions about your dosage or need adjustments, contact your healthcare provider for guidance. If you want to talk to a provider right away, consider scheduling an online doctor appointment through a telehealth platform like Sesame.
If you miss a dose of mirtazapine, take it as soon as you remember unless it is close to the time for your next scheduled dose. In that case, skip the missed dose and continue your regular dosing schedule. Do not double the dose to make up for a missed one.
Take mirtazapine around the same time every day to maintain a consistent amount of medication in your body.
Continue taking mirtazapine as prescribed by your healthcare provider, even if you start feeling better. It's important to keep taking the medication as directed to manage your condition effectively.
Do not suddenly stop taking mirtazapine; this can cause withdrawal symptoms and a return of your symptoms.
If you have any concerns or questions about your medication, discuss them with your healthcare provider for medical advice and recommendations.
Store mirtazapine according to the instructions provided by your healthcare provider or pharmacist. Keep it at room temperature, away from light and moisture. Ensure the container is tightly closed and out of reach of children.
Do not use expired medication or medications that appear damaged or discolored. If you have any questions about storage, consult your healthcare provider or pharmacist for guidance.