Mirtazapine Totally Explained

Everything about Mirtazapine totally explained

Mirtazapine is an antidepressant introduced by Organon International in 1994 used for the treatment of moderate to severe depression. Mirtazapine has a tetracyclic chemical structure and is classified as a noradrenergic and specific serotonergic antidepressant (NaSSA). Mirtazapine and Ludiomil are the only tetracyclic antidepressants that have been approved by the U.S. Food and Drug Administration to treat depression. Because of its unique pharmacologic profile, mirtazapine is virtually devoid of anticholinergic effects, serotonin-related side effects, and adrenergic side effects (orthostatic hypotension and sexual dysfunction). Antihistaminic side effects of drowsiness and weight gain are prominent. It is most useful as an add-on medication to enhance the effectiveness of agents such as duloxetine and venlafaxine in severe and treatment-resistant depression. Mirtazapine is relatively safe if an overdose is taken.

Trade names

Mirtazapine is marketed under the tradenames:

Remeron in Brazil, Canada, Czech Republic, Finland, Israel, Italy, Mexico, Netherlands, Norway, Pakistan, Sweden, Switzerland, Turkey and the United States
Zispin in Ireland and the United Kingdom
Remergil in Germany
Norset in France
Rexer in Spain
Remergon in Belgium
Mirtabene in Austria
Avanza, Mirtazon and Axit in Australia
Mirtaz in India and Srilanka
Promyrtil in Chile
Noxibel in Bolivia
Remeron, Mirzaten and Mizapin Sol in Hungary

Indications

Approved use

Mirtazapine is primarily used to treat the symptoms of moderate to severe depression.

Unapproved and off-label use

There is evidence that mirtazapine can be used to treat panic disorder (PD), generalized anxiety disorder (GAD), obsessive-compulsive disorder (OCD), post traumatic stress disorder (PTSD) sleep apnea, and pruritus. Mirtazapine has been reported to be effective in the prophylactic treatment of chronic tension headache. This drug has also been shown to improve symptoms in Gastroparesis patients.

Veterinary use

Anecdotal evidence also suggests that mirtazapine may be effective in treating certain vomiting or anorexia-related conditions in dogs and cats. Any such use is still off-label, however.

Mechanism of action

It is thought to work by blocking presynaptic alpha-2 adrenergic receptors that normally inhibit the release of the neurotransmitters norepinephrine (noradrenaline) and serotonin, thereby increasing active levels in the synapse. Mirtazapine is a potent antagonist of 5-HT2 and 5-HT3 receptors. Mirtazapine has no significant affinity for the 5-HT1A and 5-HT1B receptors.

Side effects

Interestingly, its side-effect profile can be used for benefit in certain clinical situations. The drowsiness, increased appetite, and weight gain that it causes are useful in patients with depressive disorders with prominent sleep and appetite disturbances. In addition, it's quite useful in patient situations in which patients suffer from nausea, since it also antagonizes the 5-HT₃ receptor, the target of the popular anti-emetic ondansetron (Zofran).
At lower dosages, such as 7.5 mg, mirtazapine is primarily antihistaminergic, causing sedation, which can be beneficial in depressed patients who have difficulty falling asleep. At doses higher than 15 mg, its effect is primarily in inducing the release of norepinephrine, and is thus less sedating.

Side effects occurring commonly:

Mild visual hallucinations (when taken during the day or when awake)

Increased appetite

Vivid dreams / Nightmares as a result of regular intake

Depersonalization / Derealization (for example feeling unreal, in a dream-like state)

Weight gain

Increase in cholesterol, independent of weight gain

Drowsiness, especially at lower doses and during the first few weeks of treatment

Dizziness, coupled often with the effects of sickness

Headache

General or local swelling

Side effects occurring rarely:

Excessive urinating when taken with alcohol

Mania

Seizures

Tremor

Muscle twitching and Restless Legs Syndrome

Pins and needles

Rash and skin eruptions

Pain in the joints or muscles

Low blood pressure

Higher blood pressure

Obesity

Dangerous side effects

Any of these side effects requires urgent medical attention. Medical advice is also required for taper-off instructions: sudden withdrawal from antidepressants can cause serious symptoms. However, sudden withdrawal can be used, under appropriate medical supervision, when the risks of continuing the antidepressant during a 'taper-off' phase are too great.

An allergic reaction; signs of swelling of the lips, face and tongue, difficulty in breathing, rash or itching (especially affecting the whole body) or feeling faint

Signs of infection such as fever, sore throat, mouth ulcers or stomach upset

Jaundice (yellowing of the skin and/or eyes)

Agranulocytosis

Dosage

The usual starting dose for mirtazapine is 15 mg once daily, usually at bedtime (because of its sedative nature and the possibility of disturbed visual perception). Doses may be increased, following medical advice, every 1-2 weeks up to a dose of 45 mg. It may be taken with or without food. Dispersible tablets (SolTab orally disintegrating tablets) can even be taken without water.

Pregnancy and lactation

Pregnancy : Sufficient data in humans is lacking. The use should be justified by the severity of the condition to be treated.

Lactation : Sufficient data in humans is also lacking. Additionally, Mirtazapine may be found in the maternal milk in significant concentrations. The use in breastfeeding women should be carefully weighed against possible risks.

Interactions with other drugs

Because of the sedative effects of Mirtazapine, excessive sedation may result when it's used with other sedating substances, such as alcohol or benzodiazepines.
According to official prescribing information from Organon, Mirtazapine shouldn't be used within 14 days of the use of an MAOI because of the risk of serious effects such as hypertensive emergency and hyperthermia.

Further Information

Get more info on 'Mirtazapine'.

External Link Exchanges

Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:

<a href="http://mirtazapine.totallyexplained.com">Mirtazapine Totally Explained</a>

Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned.