Table 2.

Published class I and class II evidence of pharmacological treatment for DNP

Drugs	Trial size	Dosage	Study design	Result	NNT	EFNS	AAN
Pregabalin	146	300 mg	Parallel, 8 weeks	Pregabalin > placebo103	3.9	I	I
	338	75, 300, 600 mg	Parallel, 5 weeks	Pregabalin (300, 600 mg) > placebo104	300 mg: 3.6 600 mg: 3.3	I	I
	246	150, 600 mg	Parallel, 6 weeks	Pregabalin (600 mg) > placebo105	600 mg: 4.2	I	I
	338	Fixed or Flexible: 150 – 600 mg	Parallel, 12 weeks	Fixed and flexible > placebo106	3.6		II
	167	600 mg	Parallel, 13 weeks	Pregabalin (600 mg) > placebo107		I	I
	396	150, 300, 600 mg	Parallel, 12 weeks	Pregabalin (600 mg) > placebo108	600 mg: 6.3
Gabapentin	165	< 3600 mg	Parallel, 8 weeks	Gabapentin > placebo109	4	I	I
	40	900 mg	Crossover, 2×6 weeks	Gabapentin = placebo70			II
Lamotrigine	59	< 400 mg	Parallel, 8 weeks	Lamotrigine > placebo72	4	I	II
	360	200, 300, 400 mg	Parallel, 19 weeks	Lamotrigine = placebo71		I	I
	53	200 mg vs amitriptyline 75 mg	Parallel, 6 weeks	Lamotrigine = amitriptyline110		II
Valproate	52	600–>1200 mg	Parallel, 4 weeks	Valproate > placebo73		II	II
	39	500 mg	Parallel, 16 weeks	Valproate > placebo74		II	II
	31	1500 mg	Parallel, 4 weeks	Valproate = placebo75		I
Amitriptyline	29	≤ 150mg	Crossover, 2×6 weeks	Amitriptyline > placebo78	2.1		II
	24	25–75 mg	Crossover, 2×6 weeks	Amitriptyline > placebo111			II
	19	75 mg	3-phase, crossover amitriptyline and maprotiline	Amitriptyline > Maprotiline > placebo80			I
Desipramine	20	Average 201 mg	Crossover, 2×6 weeks	Desipramine > placebo112	2.2		II
Venlafaxine ER	244	150–225 mg	Parallel, 6 weeks	Venlafaxine > placebo113	4.5	I	I
	60	75–150 mg	Parallel, 8 weeks	Venlafaxine > placebo114		II
Venlafaxine + gabapentin	11 and 42		Parallel, 2×8 weeks	Venlafaxine+gabapentin > placebo in gabapentin unresponsive patients115			II and III
Duloxetine	457	20, 60, 120 mg	Parallel, 12 weeks	Duloxetine (60mg, 120 mg) > placebo116	60 mg: 4.3 120 mg: 3.8	I	II
	348	60 mg, 120 mg	Parallel, 12 weeks	Duloxetine (60mg, 120 mg) > placebo117	60 mg: 11 120 mg: 5	I	I
	334	60 mg, 120 mg	Parallel, 12 weeks	Duloxetine (60mg, 120 mg) > placebo118	60 mg: 6.3 120 mg: 3.8	I	II
Oxycodone CR	159	10–100 mg	Parallel, 6 weeks	Oxycodone > placebo119	N/A	I	II
	338	10–80 mg with gabapentin (100–3600 mg)	Parallel, 12 weeks	Oxycodone + gabapentin > placebo + gabapentin120		I	I
Morphine sulfate	57	120 morphine, 60 mg morphine +2400 mg gabapentin, 3600 mg gabapentin	Crossover, 4×4 weeks	Morphine + gabapentin>morphine>gabapentin>placebo81		I	II
Tramadol	127	100–400 mg (mean 210 mg)	Parallel, 6 weeks	Tramadol > placebo121	3.1		II
	45	200–400 mg	Crossover, 2×6 weeks	Tramadol > placebo122	4.3		II
	311	37.5 mg + 325 mg acetaminophen	Parallel, 8 weeks	Tramadol/APAP > placebo123		I
Dextromethorphan	19	400 mg	Crossover, 2×9 weeks	Dextromethorphan > placebo124	3.2	I	I
	14	Mean 381 mg	Crossover, 2×6 weeks	Dextromethorphan > placebo125	4	I	II
Capsaicin 0.075%	252	0.075% qid	Parallel, 8 weeks	Capsaicin > placebo126	NA
	22	0.075% qid	Parallel, 8 weeks	Capsaicin > placebo82			I
Isosorbide dinitrate	22	30 mg	Crossover, 2×4 weeks	Isosorbide dinitrate > placebo84			I
Glyceryl trinitrate	48		Crossover, 2×4 weeks	Glyceryl trinitrate> placebo85		II
ABT-594	266	150, 225, 300 mg bid	Parallel, 7 weeks	ABT-594>placebo86		I
Botulinum toxin	18	Fifty units of subtype A in 1.2 mL 0.9% saline intradermally into each foot, each injection 4 U subtype A	Crossover, 12×12 weeks	Botulinum toxin > placebo127		II
Levodopa	25	100 mg levodopa plus benserazide 25 mg tid	Parallel, 28 days	Levodopa + benserazide > placebo128		II

DNP = Diabetic neuropathic pain