- Introduction to Mirtazapine
- Beneficial Effects of Mirtazapine
- 1) Mirtazapine Improves Depression
- 2) Mirtazapine May Improve Anxiety and Panic Disorder
- 3) Mirtazapine Benefits Memory and Retaining of Positive Information
- 4) Mirtazapine Improves Chronic Pain
- 5) Mirtazapine Improves PTSD Symptoms When Compared to Placebo
- 6) Mirtazapine Improves OCD Symptoms
- 7) Mirtazapine Reduces Intensity and Frequency of Migraines
- 8) Mirtazapine Provides Itching Relief
- 9) Mirtazapine’s Sedative Effects Improve Insomnia
- 10) Mirtazapine Improves Low Appetite/Anorexia Nervosa Associated with Depression
- Side Effects, and Possible Negative Effects of Mirtazapine
- Interactions and Synergies with Mirtazapine
- Personal Experiences with Mirtazapine (from the writer)
- Mirtazapine and Genetics
- A Note From Joe
Introduction to Mirtazapine
Mirtazapine is not often a first-line treatment. Mirtazapine is a particularly useful choice in patients who have had sexual dysfunction while using other antidepressants, or patients that have insomnia in combination with their depression(R).
Mirtazapine is not only effective, but generally tolerable when it comes to side effects in comparison to other antidepressants (R).
Mirtazapine works quickly, with symptom relief beginning within a week. This is a much faster onset of action compared to medications in the SSRI class (R).
It seems to be safe and effective for long-term use, and is comparable in effectiveness to drugs such as amitriptyline, clomipramine, doxepin, fluoxetine, paroxetine, citalopram, and venlafaxine with a better side effect profile (R).
An important thing to consider when making the comparison between mirtazapine and SSRIs is that mirtazapine has no sexual side effects, and an all-around better side effect profile when compared to SSRIs (R).
Beneficial Effects of Mirtazapine
1) Mirtazapine Improves Depression
In eight controlled trials of major depression, Mirtazapine improvement began in the first week of treatment and was significantly greater than placebo (R).
Mirtazapine had an efficacy profile that was shown to surpass multiple SSRIs and SNRIs, in earlier weeks of therapy. The drug is equivalent in efficacy to tricyclic antidepressants, with a better tolerability profile (R).
Compared to SSRIs, patients using mirtazapine had a 74 percent greater likelihood of achieving remission during the first two weeks of therapy (R).
Mirtazapine reduces depression by:
- Blocking α2-adrenoceptors, which lead to enhanced release of norepinephrine and serotonin (R).
- Potent blocking of serotonin 5-HT2 and 5-HT3, which increases stimulation of the 5-HT1 receptor (R).
- Blocking the histamine H1 receptors, causing a sedative effect, and improvement of sleep. (R).
- Activating mu- and kappa3-opioid receptors, which reduces pain (R).
- Decreasing glutamate in rats (R).
2) Mirtazapine May Improve Anxiety and Panic Disorder
Mirtazapine is not necessarily seen as a first-line treatment for anxiety patients.
Mirtazapine has been found to be effective in many types of anxiety, and the symptoms that accompany it.
In a study of 44 patients with generalized anxiety disorder who had an average duration of the symptoms for 12.3 years, the positive response rate was as high as 79.5 percent. Approximately 44 percent of patients felt a full relief of symptoms. It also helped people who were previously on benzodiazepines get off of them (R).
Here are a few clinical examples in which Mirtazapine has had a positive effect on anxiety disorders:
- Mirtazapine reduced pre-surgery anxiety and insomnia more than placebo and comparatively to diazepam (R).
- Mirtazapine reduced anxiety, sleeping difficulties, and nausea caused by chemotherapy (R).
- Mirtazapine helped 7 out of 10 people with major depression, who also suffered from generalized anxiety disorder and panic disorder (small, open-label pilot study) (R, R2).
- Mirtazapine reduced the intensity of panic attacks in patients with panic disorder, showing effectiveness comparable to fluoxetine (R, R2, R3, R4 R5).
- Three out of six patients with severe, chronic PTSD benefited from mirtazapine (R, R2).
- Social anxiety was reduced in 5 out of 12 patients (R).
Mirtazapine’s Anti-Anxiety Mechanisms:
- Blocks 5-HT2a and 5-HT3 receptors (R).
- Significantly increased GABA and decreased glutamate (nucleus accumbens, rats)(R).
3) Mirtazapine Benefits Memory and Retaining of Positive Information
In rat models, Mirtazapine has shown to have a distinct memory-improving activity, or memory restoring effects (R).
Depressed patients often retain more negative information about themselves. Mirtazapine was shown to induce an effect in patients more likely to retain positive information regarding themselves (R).
4) Mirtazapine Improves Chronic Pain
Antidepressants have been used as non-traditional pain relief options in patients with chronic pain. Mirtazapine has shown promising results in the treatment of chronic pain. A patient’s chronic back pain did not respond to the drug amitriptyline but responded to mirtazapine treatment (R).
Mirtazapine activates the k-opioid receptors, which may be a large contributor to the pain relieving effects (R).
5) Mirtazapine Improves PTSD Symptoms When Compared to Placebo
Mirtazapine is more effective than placebo on some measures of PTSD. This same study also concluded that mirtazapine also improved some general anxiety disorder symptoms (R).
After four weeks, three out of six patients reported a significant reduction in the severity of PTSD symptoms (R).
6) Mirtazapine Improves OCD Symptoms
The majority of the studies done on the treatment of OCD with mirtazapine have been smaller, but have concluded the possibility of mirtazapine being an effective therapy for OCD (R).
In 49 patients, mirtazapine in combination with citalopram resulted in “much improved” or “very much improved” ratings by the fourth week, compared to the citalopram and placebo group that did not see real results until the eighth week (R).
7) Mirtazapine Reduces Intensity and Frequency of Migraines
Mirtazapine decreased the frequency and intensity of migraines.
Mirtazapine is thought to prevent migraines through histamine and 5-HT2 receptors, and treats migraines through the 5-HT1 receptor (R).
8) Mirtazapine Provides Itching Relief
9) Mirtazapine’s Sedative Effects Improve Insomnia
10) Mirtazapine Improves Low Appetite/Anorexia Nervosa Associated with Depression
Mirtazapine may have an appetite stimulating effect in patients taking it. Weight gain and increased appetite are among the most commonly reported side effects of the medication (R).
The appetite-stimulating effects of mirtazapine and antidepressant effects of the medication show it as a promising drug in use of patients that have anorexia caused by depression, or depression caused by anorexia (R).
Mirtazapine worked in some case studies of anorexia nervosa (R).
Mechanisms of mirtazapine-induced weight gain:
- Blocking 5HT2C and H1 receptors (R).
- Mirtazapine possibly reduces the energy your body expends, which results in weight gain (R).
Mirtazapine seems to be more sedating at lower doses and more activating at higher doses.In patients simply trying to treat insomnia, it is not unheard of to use 7.5mg. The normal starting dosage is 15-30mg and can be titrated up to a maximum dosage of 45mg (R).
Side Effects, and Possible Negative Effects of Mirtazapine
While Mirtazapine is seen as more tolerable than SSRIs, common side effects from Mirtazapine include drowsiness, dizziness, strange dreams, vision changes, dry mouth, constipation, increased appetite and/or weight gain (R).
A study that observed a significant increase in weight gain in the first week of therapy (R).
Mirtazapine May Reduce Ability to Recognize Emotional Cues
Mirtazapine significantly impaired the recognition of fearful facial expression. This shows that mirtazapine, similarly to SSRIs, may reduce a patient’s ability to recognize emotional cues and signs in other people (R).
Mirtazapine May Increase the Inflammatory Process
Mirtazapine increases TNF-α, which is synthesized by lymphocytes and monocytes, and may increase the inflammatory process. TNF-α is the main factor in processes associated with several inflammatory diseases which could result in implications of mirtazapine treatment in these patients (R).
Interactions and Synergies with Mirtazapine
In a study aimed at the treatment of resistant melancholia, a case study showed that when a woman was given a high dosage of a tricyclic antidepressant in combination with mirtazapine, lithium, and partial sleep deprivation, the patient achieved complete remission after six weeks (R).
Mirtazapine as a combination with other antidepressants has shown improved treatment of depression. Mirtazapine in conjunction with SNRIs has been seen to successfully treat treatment-resistant major depression (R, R2).
Alcohol increases the nervous system side effects of mirtazapine.
- Clinical worsening and suicide risk (R).
- Agranulocytosis: In very rare cases agranulocytosis has been observed with mirtazapine treatment. If a patient develops a sore throat, fever, stomatitis, or other signs of infection along with a low WBC, treatment with mirtazapine should be discontinued and monitored. In the cases observed the agranulocytosis was reversed upon cessation (R).
- Serotonin Syndrome: Mirtazapine should be avoided with other serotonin increasing drugs, and monitored closely in conjunction with SSRIs (R).
- Angle-Closure Glaucoma: Mirtazapine should be carefully monitored in patients with angle-closure glaucoma, and in rare cases, mirtazapine could cause angle-closure glaucoma (R).
- QT Prolongation and Torsades de Pointes: Caution should be exercised before starting this medication in patients with known heart disease, or family history of QT prolongation, and in concurrent use of other drugs believed to affect the QTc interval (R).
- High Cholesterol: Mirtazapine may significantly elevate blood triglyceride and total cholesterol levels. Patients with preexisting high levels of fats in the blood should be monitored closely (R).
Personal Experiences with Mirtazapine (from the writer)
Mirtazapine and I didn’t seem to respond to each other particularly well. I was on a dose of 30mg once daily before bed.
I could only give it a month from starting it before I had to discontinue it due to side effects. The main problem that I found myself facing was daytime sleepiness that strangely wasn’t even combatted by the ADHD medication I was taking in conjunction with it.
I found a relatively quick relief of depression symptoms and anxiety symptoms, but it was traded for a constant sleepiness and lethargy.
It felt as if I honestly was just entirely too tired to worry about my depression and anxiety.
This is not to say your experience won’t differ; many others report having positive effects and even an activating effect from the medication.
Mirtazapine and Genetics
A Note From Joe
I don’t recommend taking mirtazapine unless you’ve tried other ‘natural’ therapies first.
Speak to your doctor before you take any drugs.