Inclusion Criteria

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