ANALGESIC EFFECT OF SUBARACHNOID NEOSTIGMINE IN 2 PATIENTS WITH CANCER PAIN

Two patients suffering with severe pain due to metastatic abdominal ne oplasm were selected to examine whether subarachnoid neostigmine provi ded effective pain relief. Neostigmine was injected through a catheter introduced into the subarachnoid space at L4-L5. Patients were monito red for changes in arterial blood pressure, cardiac and respiratory ra tes, body temperature, level of consciousness and neurologic change. P ain was classified by the patients on a verbal four-grade scale, and a nalgesia was classified on a verbal three-grade scale. Complete pain r elief was obtained 2 h after neostigmine (0.2 mg) in one patient and 4 h after neostigmine (0.1 mg) in the second patient. Pain of mild inte nsity returned 20 and 22 h after drug administration, respectively. Ga strointestinal discomfort was observed in both cases, but nausea and v omiting occurred only in the patient treated with the highest dose of neostigmine. No significant change in the monitored parameters was obs erved, except for a 6-h period of decreased blood pressure in the pati ent treated with the lower dose of neostigmine which required no speci fic treatment. The results obtained in these anecdotal cases indicate that subarachnoid neostigmine may provide analgesia in patients with p ain arising from neoplasia, but further studies using controlled trial s are needed before the drug is brought into clinical use.