DISEASE CHARACTERISTICS:

• Has received or is currently receiving neurotoxic chemotherapy, including taxanes (e.g., paclitaxel or docetaxel), platinum-based compounds (e.g., carboplatin, cisplatin, or oxaliplatin), or vinca alkaloids (e.g., vincristine or vinblastine)

• Pain or symptoms of peripheral neuropathy of at least 1 month duration attributed to chemotherapy-induced peripheral neuropathy

  • Average daily pain rating of at least 4 out of 10 using the pain numerical rating scale (where 0 is no pain and 10 is the worst pain possible) OR

  • Evidence of peripheral neuropathy of at least grade 1 out of 3 by ECOG Common

    • Toxicity Criteria for sensory neuropathy

• No other identified causes of painful paresthesia existing prior to chemotherapy

  • No radiotherapy-induced or malignant plexopathy
  • No lumbar or cervical radiculopathy

  • No pre-existing peripheral neuropathy of another etiology, including:

    • B12 deficiency
    • AIDS
    • Monoclonal gammopathy
    • Diabetes
    • Heavy metal poisoning
    • Amyloidosis
    • Syphilis
    • Hyperthyroidism or hypothyroidism
    • Inherited neuropathy

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• Not specified

Life expectancy:

• At least 6 months

Hematopoietic:

• Not specified

Hepatic:

• Not specified

Renal:

• Creatinine no greater than 1.5 times upper limit of normal

Other:

• No prior allergic reaction or intolerance to gabapentin
• No significant psychiatric illness (e.g., mania, psychosis, or schizophrenia) that would preclude study compliance
• No extreme difficulty swallowing pills
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• See Disease Characteristics

Endocrine therapy:

• Not specified

Radiotherapy:

• See Disease Characteristics

Surgery:

• Not specified

Other:

• More than 30 days since prior investigational agent for pain control
• Concurrent selective serotonin reuptake inhibitors allowed
• Concurrent nonsteroidal anti-inflammatory drugs allowed
• No concurrent tricyclic antidepressant (e.g., amitriptyline, nortriptyline, or desipramine)*
• No concurrent monoamine oxidase inhibitor*
• No concurrent opioid analgesic*
• No other concurrent adjuvant analgesic (e.g., anticonvulsant, clonazepam, or mexiletine)*
• No concurrent topical analgesics (e.g., lidocaine gel or lidocaine patch)*
• No concurrent amifostine
• No concurrent investigational agent for pain control NOTE: * For pain or symptoms due to chemotherapy-induced peripheral neuropathy