SSNaRI - Selective Serotonin and Noradrenaline Reuptake Inhibitor (Wiki)

Also referred to as a Serotonin and Noradrenaline Reuptake Inhibitor (SNRI)
Also referred to as a Serotonin and Noradrenaline Reuptake Inhibitor (SNaRI)
Also referred to as a Selective Serotonin and Noradrenaline Reuptake Inhibitor (SSNRI)

Please note: Dosage equivalents are provided for certain drugs below and are denoted as unit equivalents, i.e. one unit of drug x is roughly the equivalent as one unit of drug y, where the dosage equal to one unit varies.

Selective Serotonin and Noradrenaline Reuptake Inhibitors work by decreasing the breaking down of the monoamine neurotransmitters serotonin and noradrenaline within the brain, thus increasing the levels of said neurotransmitters available for the concerned neurons to soak in, as so to speak.

Since these drugs act on noradrenaline, they can be used for the treatment of chronic neuropathic pain, something that the more popular SSRI antidepressants cannot tackle. These medications appear to be better tolerated and more effective than SSRI antidepressants. However, by the same token they share many of the withdrawal symptoms that SSRI antidepressants typically have.


Desvenlafaxine (Wiki)

Brand names: Pristiq
Formula: C16H25NO2
Half life: Unknown
Single unit dose: Unknown
Recommended outpatient dose: Unknown
Maximum outpatient dose: Unknown

I have little information on this drug at this time except that it is currently under development and that it is a metabolite of Venlafaxine. It was approved for use in February 2008.

Duloxetine (Wiki)

Brand names: Ariclaim®, Cymbalta®, Yentreve®
Formula: C18H19NOS
Half life: ~ 8 to 17 hours (vague figure)
Single unit dose: Unknown
Recommended outpatient dose: 40mg per day [Not Verified]
Maximum outpatient dose: 80mg per day [Not Verified]
No. 5 most prescribed antidepressant in USA, 2006

Seen as the newer version of the drug venlafaxine, Duloxetine is interesting in that it manipulates the monoamine neurotransmitters serotonin and noradrenaline in near equal amounts; it also effects dopamine reuptake, but to a far less significant extent.

Rather appealingly, Duloxetine is weight neutral in the majority of cases and additionally has a a generally small side effect profile, the most common side effects being somnolence, nausea and a dry mouth.

Milnacipran (Wiki)

Brand names: Ixel®
Formula: C15H22N2O
Half life: ~ 8 hours
Single unit dose: Unknown
Recommended outpatient dose: 100mg per day [Not Verified]
Maximum outpatient dose: Unknown

First made available in the latter half of 1998, milnacipran inhibits the reuptake of the monoamine neurotransmitters noradrenaline and serotonin in a rough ratio of three to one. This antidepressant is typically found to be superior to SSRI drugs in alleviating the symptoms of depressive illnesses, but is thought to be inferior to the tricyclic antidepressant clomipramine (and equal to the tricyclic antidepressant imipramine).

As with other drugs of its class, milnacipran can be used to treat chronic pain and further to this is seemingly effective as a treatment for the conditions Fibromyalgia (where it alleviates the symptoms of fatigue, a depressed mood and pain) and Lupus (where it alleviates the symptom of pain and helps to create a sense of euphoria); the latter condition is currently under investigation in reference to this drug, at time of writing in July 2006.

Common side effects of milnacipran therapy include nausea, vertigo, anxiety, shivering, itching, testicular pains and dysuria. Interestingly, it seems to be neutral when it comers to ones libido and associated functions. Compared to tricyclic antidepressants, milnacipran exhibits far fewer cardiovascular and/or anticholinergic side effects. Psychotic patients should be monitored closely as delerium can be induced through milnacipran therapy and agitation can be amplified, usually giving cause for a supplementary tranquilliser therapy to be initiated. Interestingly, whilst the drug does not usually cause sedation, it does seem to improve the quality of sleep experienced by patients.

Nefazodone (Wiki)

Brand names: Dutonin®, Menfazona®, Nefadar®, Nefirel®, Reseril®, Rulivan®, Serzone®
Formula: C25H32ClN5O2
Half life: ~ 2 to 4 hours
Single unit dose: Unknown
Recommended outpatient dose: 200mg per day [Verified]
Maximum outpatient dose: 600mg per day [Verified]

Most closely related to the tetracyclic antidepressant trazodone, nefazodone is fairly novel in its therapeutic effects. Due to a potentially fatal but small possibility of liver damage, this drug was withdrawn from sale to some extent in 2003 but is still readily available the world over. This particular antidepressant is neutral in various fields where most others are not; it tends not to cause sexual dysfunction in patients and tends not to have any impact on ones quality of sleep; it also proved to be effective where more conventional antidepressants failed.