SNRI
Posted On March 7, 2020
SNRI
- Serotonin-Norepihephrine reuptake inhibitor
- Little or no cholinergic or histaminergic effect
- Duloxetine, Venlafaxine, Desyenlafaxine has more inhibition of Serotonin uptake.
- Levomilnacipran preferentially block reuptake of norepinephrine
Duloxetine (Cymbalta)
- Highly protein bound
- Mainly cleared by liver, <1% excreted in urine. Avoid in liver disease, and CrCl <30
- Available in generic capsule: 20, 30, 60 mg cap
- Cost about $15 for 30 cap
- Indicated for: neuropathic painy, fibromyalgia, anxiety, depression, chronic musculoskeletal pain
- Off label use: stress incontinence
Venlafaxine (Effexor)
- At 75 mg daily, behaves like “SSRI”
- High dose: over 225 mg qd, significant effect on norepinephrine transporter
- Clearance: liver and kidney. 34% excreted in urine. Dose reduction need in liver and kidney diseases.
- Available in generic XR: 37.5, 75, 150 mg
- Cost about $30 for 30 cap
- Indicated for: neuropathic pain, depression, Panic, anxiety
- OPff label use: migraine prevention, narcolepsy with cataplexy, OCD, premenstrual dysphoric disorder. vasomotor sympotms with menopause, PTSD
Desvenlafaxine (Pristiq)
- Clearance: liver and kidney, 45% excreted unchanged in urine
- chronic kidney disease: CrCl <30 and end stage renal disease 25 mg qd, or 50 mg qod
- Start dose: 50 mg qd, up to 400 mg qd.
- Available in generic ER: 25, 50, 100 mg
- Cost about $25 for 30 tabs
Milnacipran (Savella)
- Dose: start 12.5 mg qd, may increase daily by 12.5 mg per day, up to 100 mg bid
- Available in brand: 12.5, 25, 50, 100 mg tab
- Cost: over $400 per month
- Excretion: 58% excreted unchanged in urine
- Kidney problem: severe CrCl <29, reduce dose to 25 mg bid
- end stage renal disease: use not recommended.