Acute Zoster Pain (AZP) and Post-Herpetic Neuralgia (PHN) in the Course of Lymphoproliferative Disorders (LPD): Durable Pain Relief Provided by Oxycodone in Patients Unresponsive to Standard Therapy.
Authors: Niscola Pasquale , Romani Claudio , Perrotti Alessio Pio , Poeta Giovanni Del , Cartoni Claudio , Palombi Massimiliano , Giovannini Marco , Cupelli Luca , De Fabritiis Paolo 
Published: October 2019

Abstract
Background. PHN and AZP are significant neuropathic pain syndromes associated with LPD. Some pathways in the pathological process, including a peripheral nerve injury and a central sensitisation, suggest that an appropriate approach should include multiple agents having different mechanisms of action. Anticonvulsants, mainly gabapentin (GB) and pregabalin (PGB), are indicated for the AZP and PHN management, while the role of opioids and topical analgesics was not definitively established.
Case series. There were 5 patients (2 NHL, 1 ALL, 1 CLL, 1 MM) with median age of 69 (52–83) years. Some clinical features concernig the patient’s pain histories are detailed in table 1. Patient 1 and 2 presented long lasting PHN unrelieved by GB and PGB, alone or associated with tramadol in the second case. The patient 1 kept under our attention complaining a constant deep, aching burning sensation, spontaneous shooting pain and a superficial dysesthetic sufferance evoked by light touch or wearing clothes. Oxycodone was administered at initial dose of 10 mg twice daily and the titrated until an acceptable pain relief was achieved. No remarkable side effects were recorded. However persisting allodynia was reported by the two PHN patients, for which the application of topical capsaicin 0.075 percent cream was started, obtaining after one week a complete resolution of allodynia. Burning was the main side effect, improving after the first week of capsaicin topical application. Patient 2 received oxycodone at initial doses 5 mg thrice achieving a rapid pain relief. Patients 3, 4 and 5 presented AZP unresponsive to GB or PGB alone. Overall, in all patients, the median reported pain rate was 7 (4 – 9), on a 0 to 10 pain scale. Two patients need a slight increase of the dosage.
Conclusion. Although the short follow-up and the small size of the series, some suggestions do appear:
an opioid should be taken into account in patients with AZP or PHN; in this light, oxycodone could represent a suitable potential option, although no randomised studies have claimed its superiority to others opioid; topical capsaicine cream can improve allodynia.
However, from these anecdotic observations some questions, such as the opioid of choice in this setting, the best timing and duration of therapy, the choice of other drugs to be associated with oxycodone or other opiods, remain to explore and may represent the basis of further research on this specific topic.
Table 1: outcome of the patient’s zoster-related pain syndromes Patient Primary Analgesic Therapy Basal pain rate Oxy initial doses (mg) Time to Response [Days] Mean Doses (Days of Treatment) Last Pain Rate Oxy: Oxycodone; PGB: Pregabalin; GB: Gabapentin; NSAIDs: Non-Steroidal Antinflammatory Drugs; AMP: Acetaminophen. ° Reduction of almost 50% of pain rate with respect to the baseline level. 1 PGB (1800 mg) 9 20 2 30 mg (240) 0–1 2 GB (1200 mg) 8 15 3 15 mg (95) 1–2 3 GB (900 mg)+ AMP (3000 mg) 7 15 1 15 mg (95) 0 4 PGB (300) 7 15 1 15 mg (95) 0 5 GB (1800) + NSAIDs 4 15 3 15 mg (95) 1