Table 4.

Adjuvant therapies

Medication	Indication	Dosage Range	Clinical Pearls
Antidepressants
Amitriptyline   (Elavil)	Diabetic  peripheral  neuropathy (off-  label)	Start 10 mg/d Titrate at tolerated,  lower doses are  recommended	Caution anticholinergic  effects/burden
Nortriptyline   (Pamelor)	Diabetic  peripheral  neuropathy (off-  label) Postherpetic  neuralgia (off-  label)	Start 10–20 mg/d  (bedtime) Titrate every 3–5 d as  tolerated in 10 mg  increments Max 160 mg/d	Fewer anticholinergic effects than other tricyclic antidepressants Preferred in older adult population; however, still need to monitor for anticholinergic effects/ burden
Venlafaxine ER   (Effexor XR)	Diabetic  peripheral  neuropathy (off-  label)	Start 37.5 mg/d Titrate to 75–225 mg/d	Monitor blood pressure, and for increased anxiety or insomnia May impair platelet aggregation, monitor for bruising and bleeding Associated with hyponatremia, monitor sodium levels upon initiation, dose changes and periodically during therapy
Duloxetine   (Cymbalta)	Diabetic  peripheral  neuropathy Fibromyalgia	Start 30–60 mg/d Titrate to 60–120 mg/d	Preferred SNRI for older adults Well tolerated with reduced incidence of SNRI typical side effects Association with hyponatremia remains the same as other SNRIs
Anticonvulsants
Carbamazepine   (Tegretol)	Trigeminal  neuralgia	Start 200 mg/d BID Titrate to 400–  800 mg/d BID	Several drug interactions Nausea, edema, insomnia, agitation, Stevens-Johnson syndrome
Oxcarbazepine   (Trileptal)	Trigeminal  neuralgia (off-  label use)	Start 300–600 mg/d  BID Titrate to 1500–  1800 mg/d BID	Elevated blood pressure,  dizziness, drowsiness,  headache, agitation,  nausea, constipation,  vomiting
Lamotrigine   (Lamictal)	Trigeminal  neuralgia	Start 5 mg/d Titrate to 200–  600 mg/d	Monitor for  hypersensitivity  reactions, (rash, acute  urticarial, and extensive  pruritus); risk is higher  with the  coadministration of  valproic acid
Gabapentin   (Neurontin)	Postherpetic  neuralgia Diabetic  peripheral  neuropathy (off-  label) Fibromyalgia (off-  label)	Start 300 mg/d TID Titrate to 1800–  3600 mg/d TID	Monitor renal function as gabapentin should be dose adjusted when CrCl <60 mL/min Caution increased risk for falls due to dizziness and somnolence
Pregabalin   (Lyrica)	Postherpetic  neuralgia Diabetic  peripheral  neuropathy Fibromyalgia	Start 150 mg/d BID-  TID Titrate to 150–  300 mg/d BID–TID	Controlled substance C-IV Monitor renal function as gabapentin should be dose adjusted when CrCl <60 mL/min Caution increased risk for falls due to dizziness and somnolence

Abbreviations: BID, twice a day; CrCl, creatinine clearance; SNRI, serotonin-norepinephrine reup-take inhibitors; TID, 3 times a day.