Table 4

Treatment for pain associated with DSPN (15,16,20,86,87)

Drug class	Agent	Dose		NNT range 30–50% improvement^**	Common adverse events	Major adverse events
Drug class	Agent	Initial	Effective	NNT range 30–50% improvement^**	Common adverse events	Major adverse events
Anticonvulsants
	Pregabalin^* (15,86,88–94)	25–75 mg, 1–3×/day	300–600 mg/day	3.3–8.3	• Somnolence	• Angioedema
					• Dizziness	• Hepatotoxicity
					• Peripheral edema	• Rhabdomyolysis
					• Headache	• Suicidal thoughts and behavior
					• Ataxia	• Seizures after rapid discontinuation
					• Fatigue	• Thrombocytopenia
					• Xerostomia
					• Weight gain
	Gabapentin (15,86,96,105–111)	100–300 mg, 1–3×/day	900–3,600 mg/day	3.3–7.2	• Somnolence	• Stevens-Johnson syndrome
					• Dizziness	• Suicidal thoughts and behavior
					• Ataxia	• Seizures after rapid discontinuation
					• Fatigue
Antidepressants
Serotonin-norepinephrine reuptake inhibitors	Duloxetine^* (15,86,94,96,98–101)	20–30 mg/day	60–120 mg/day	3.8–11	• Nausea	• Stevens-Johnson syndrome
					• Somnolence	• Hepatotoxicity
					• Dizziness	• Hypertensive crisis
					• Constipation	• Gastrointestinal hemorrhage
					• Dyspepsia	• Delirium
					• Diarrhea	• Myocardial infarction
					• Xerostomia	• Cardiac arrhythmias
					• Anorexia	• Glaucoma
					• Headache	• Suicidal thoughts and behavior
					• Diaphoresis	• Shift to mania in patients with bipolar disorder
					• Insomnia	• Seizures
					• Fatigue	• Severe hyponatremia
					• Decreased libido	• Fragility bone fractures
						• Serotonin syndrome
						• Neuroleptic malignant syndrome
	Venlafaxine (15,16,20,86,87,126,127)	37.5 mg/day	75–225 mg/day	5.2–8.4	• Nausea	• Same as duloxetine
					• Somnolence
					• Dizziness
					• Constipation
					• Dyspepsia
					• Diarrhea
					• Xerostomia
					• Anorexia
					• Headache
					• Diaphoresis
					• Insomnia
					• Fatigue
					• Decreased libido
Tricyclic antidepressants	Amitriptyline (16,110,112–116)	10–25 mg/day	25–100 mg/day	2.1–4.2	• Xerostomia	• Delirium
					• Somnolence	• Cardiac arrhythmias
					• Fatigue	• Conduction abnormalities
					• Headache	• Myocardial infarction
					• Dizziness	• Heart failure exacerbation
					• Insomnia	• Stroke
					• Orthostatic hypotension	• Seizures
					• Anorexia	• Hepatotoxicity
					• Nausea	• Bone marrow suppression
					• Urinary retention	• Suicidal thoughts and behavior
					• Constipation	• Shift to mania in bipolar disorder
					• Blurred vision	• Neuroleptic malignant syndrome
					• Accommodation	• Serotonin syndrome
					• Disturbance	• Severe hyponatremia
					• Mydriasis	• Fragility bone fractures
					• Weight gain
	Desipramine (113,118–121,122)				• Same as above	• Same as above
	Nortriptyline (15,16,86,87,113,114,120,121,123)				• Same as above	• Same as above
Opioids
	Tramadol (15,16,86,87,109,130)	50 mg, 1–2×/day	210 mg/day	3.1–6.4	• Somnolence	• Confusion
					• Nausea	• Seizures
					• Vomiting	• Cardiac arrhythmias
					• Constipation	• Hypertension
					• Light-headedness	• Hypersensitivity reactions
					• Dizziness	• Stevens-Johnson syndrome
					• Headache
	Tapentadol^* (103,104,135)	Immediate release:50–100 mg, 4–6×/day	Immediate-release: day 1: 700 mg; after day 1, 60 mg/day	N/A	• Somnolence	• Respiratory depression
		Immediate release:50–100 mg, 4–6×/day	Immediate-release: day 1: 700 mg; after day 1, 60 mg/day		• Nausea	• Serotonin syndrome
		Extended release:50 mg, 2×/day	Extended release:50 mg, 2×/day		• Vomiting	• Seizures
					• Constipation	• Hypertension
					• Dizziness	• Neonatal opioid withdrawal syndrome

↵NNT, number needed to treat. *FDA approved.
↵**FDA considers 30–50% improvement to be significant.