Topical morphine for oral mucositis in children: dose finding and absorption

A Narrative Review of Pain in Pediatric Oncology: The Opioid Option

Opioid therapy is the mainstay for managing pain in pediatric oncology. This narrative review describes the current literature regarding opioids for pediatric cancer pain. The review explores the multifaceted landscape of opioid utilization in this population, including the role of opioids in certain clinical circumstances, modalities of opioid delivery, unique opioids, outpatient and at-home pain management strategies, and other key concepts such as breakthrough pain. This review highlights the importance of individualized dosing and multimodal approaches to enhance efficacy and minimize adverse effects. Drawing from a wide range of evidence, this review offers insights to optimize pediatric oncology pain management.

Natural Products for the Prevention and Treatment of Oral Mucositis-A Review

Cancer, a major world public health problem, is associated with chemotherapy treatments whose administration leads to secondary concerns, such as oral mucositis (OM). The OM disorder is characterized by the presence of ulcers in the oral mucosa that cause pain, bleeding, and difficulty in ingesting fluids and solids, or speaking. Bioactive compounds from natural sources have arisen as an effective approach for OM. This review aims to summarize the new potential application of different natural products in the prevention and treatment of OM in comparison to conventional ones, also providing a deep insight into the most recent clinical studies. Natural products, such as Aloe vera, Glycyrrhiza glabra, Camellia sinensis, Calendula officinalis, or honeybee crops, constitute examples of sources of bioactive compounds with pharmacological interest due to their well-reported activities (e.g., antimicrobial, antiviral, anti-inflammatory, analgesic, or wound healing). These activities are associated with the bioactive compounds present in their matrix (such as flavonoids), which are associated with in vivo biological activities and minimal or absent toxicity. Finally, encapsulation has arisen as a future opportunity to preserve the chemical stability and the drug bioa vailability of bioactive compounds and, most importantly, to improve the buccal retention period and the therapeutic effects.

Intravenous opioids for chemotherapy-induced severe mucositis pain in children: Systematic review and single-center case series of management with patient- or nurse-controlled analgesia (PCA/NCA)

BACKGROUND

Chemotherapy-induced oral mucositis can result in severe pain. Intravenous (IV) opioids are recommended, but management protocols vary. We systematically reviewed studies reporting IV opioid use for pain related to chemotherapy-induced severe oral mucositis in children and conducted a large single-center case series.

METHODS

Ovid MEDLINE, PubMed, and Cochrane databases were searched for studies reporting IV opioid duration and/or dose requirements for severe mucositis. Secondly, our pain service database was interrogated to describe episodes of opioid administration by patient- or nurse-controlled analgesia (PCA/NCA) for children with mucositis and cancer treatment-related pain.

RESULTS

Seventeen studies (six randomized trials, two prospective observational, three retrospective cohort, six retrospective case series) included IV opioid in 618 patients (age 0.3-22.3 years), but reported parameters varied. Mucositis severity and chemotherapy indication influenced IV opioid requirements, with duration ranging from 3 to 68 days and variable dose trajectories (hourly morphine or equivalent 0-97 mcg/kg/h). Our 7-year series included PCA/NCA for 364 episodes of severe mucositis (302 patients; age 0.12-17.2 years). Duration ranged from 1 to 107 days and dose requirements in the first 3 days from 1 to 110 mcg/kg/h morphine. Longer PCA/NCA duration was associated with: higher initial morphine requirements (ρ = 0.46 [95% CI 0.35, 0.57]); subsequent increased pain and need for ketamine co-analgesia (118/364 episodes with opioid/ketamine 13.9 [9.8-22.2] days vs opioid alone 6.0 [3.9-10.8] days; median [IQR]); but not with age or sex.

CONCLUSIONS

Management of severe mucositis pain can require prolonged IV opioid therapy. Individual and treatment-related variability in analgesic requirements highlight the need for regular review, titration, and management by specialist services.

Evaluation of topical morphine for treatment of oral mucositis in cancer patients

Introduction

Oral mucositis is a painful side effect to chemotherapy. Orally applied opioids may offer analgesia with fewer side effects than systemic opioids.

Methods

A randomized trial comparing the analgesic effect of a morphine oromucosal solution (OM) to placebo and a positive control group receiving intravenous (IV) morphine as an add-on treatment to morphine patient-controlled analgesia (PCA) in a mixed population of paediatric and adult haematology patients. All patients in the study were equipped with a morphine PCA pump and the participating patients were instructed to use this pump as an escape. Primary outcome was morphine consumption (mg/kg/hour) on the PCA pump. Secondary outcomes included pain intensity difference at rest and when performing oral hygiene, time to first PCA bolus, nutrition intake and adverse events.

Findings

A total of 60 patients (38 children <18 years) were randomized. Thirty patients were allocated to morphine OM/placebo IV (group MO), 15 patients to placebo OM/morphine IV (group MI) and 15 patients to placebo OM/placebo IV (group P). The median morphine consumption in the MO group (22.7 mcg/kg/hour 95% confidence interval (CI) 19.4-29.4 mcg/kg/hour, p = 0.38) was not significantly different from the placebo group (24.6 mcg/kg/hour 95% CI 16.8-34.4 mcg/kg/hour, p = 0.44) or the MI group (13.7 mcg/kg/hour 95% CI 9.7-37.8 mcg/kg/hour). For the secondary outcomes, the analysis of summed pain intensity difference after the first, third and fourth administrations of study medication indicated a reduction in pain for the MI group compared to the P and MO groups. No serious adverse events were reported.

Conclusion

The findings indicate that the analgesic effect of peripherally applied morphine is not significantly different from placebo, and parenteral opioids should continue to be the standard of care.

Peripherally Acting Opioids in Orofacial Pain

The activation of opioid receptors by exogenous or endogenous opioids can produce significant analgesic effects in peripheral tissues. Numerous researchers have demonstrated the expression of peripheral opioid receptors (PORs) and endogenous opioid peptides (EOPs) in the orofacial region. Growing evidence has shown the involvement of PORs and immune cell-derived EOPs in the modulation of orofacial pain. In this review, we discuss the role of PORs and EOPs in orofacial pain and the possible cellular mechanisms involved. Furthermore, the potential development of therapeutic strategies for orofacial pain is also summarized.

Opioids in the Management of Acute Pediatric Pain: An Update in a Time of Crisis

Management of acute pain in children is fundamental to our practice. Its myriad benefits include reduced suffering, improved patient satisfaction, more rapid recovery, and a reduced risk of developing postsurgical chronic pain. Although a multimodal analgesic approach is now routinely used, informed and judicious use of opioid receptor agonists remains crucial in this treatment paradigm, as long as the benefits and risks are fully understood. Further, an ongoing public health response to the current opioid crisis is required to help prevent new cases of opioid addiction, identify opioid-addicted individuals, and ensure access to effective opioid addiction treatment, while at the same time continuing to safely meet the needs of patients experiencing pain.

The role of peripheral opioid receptors in orofacial pain

Opioid receptors are widely distributed in the central and peripheral nervous systems and non-neuronal tissues. Numerous researchers have noted the pivotal role of peripheral opioid receptors (PORs) in analgesia. Accumulating evidence has shown the existence of PORs in the trigeminal nerve system, indicating that PORs may be involved in the modulation of orofacial pain. In this review, we summarise the recent evidence for the role of PORs in orofacial pain and discuss the possible cellular mechanisms.

Randomized controlled trial to compare oral analgesic requirements and patient satisfaction in using oral non-steroidal anti-inflammatory drugs versus benzydamine hydrochloride oral rinses after mandibular third molar extraction: a pilot study

Background

Third molar extraction is associated with considerable pain and discomfort, which is mostly managed with oral analgesic medication. We assessed the analgesic effect of benzydamine hydrochloride, a topical analgesic oral rinse, for controlling postoperative pain following third molar extraction.

Methods

A randomized controlled trial was conducted in 40 patients divided into two groups, for extraction of fully erupted third molar. Groups A received benzydamine hydrochloride mouthwash and group B received normal saline gargle with oral ibuprofen and paracetamol. Oral ibuprofen and paracetamol was the rescue analgesic drug in group A. Patients were evaluated on the 3^rd and 7^th post-operative days (POD) for pain using the visual analogue score (VAS), trismus, total number of analgesics consumed, and satisfaction level of patients.

Results

The VAS in groups A and B on POD3 and POD7 was 4.55 ± 2.54 and 3.95 ± 1.8, and 1.2 ± 1.64 and 0.95 ± 1.14, respectively and was statistically insignificant. The number of analgesics consumed in groups A and B on POD3 (5.25 ± 2.22 and 6.05 ± 2.43) was not statistically different from that consumed on POD7 (9.15 ± 5.93 and 10.65 ± 6.46). The p values for trismus on POD3 and POD7 were 0.609 and 0.490, respectively and those for patient satisfaction level on POD3 and POD7 were 0.283 and 0.217, respectively.

Conclusions

Benzydamine hydrochloride oral rinses do not significantly reduce intake of oral analgesics and are inadequate for pain relief following mandibular third molar extraction.

Effect of bupivacaine lozenges on oral mucositis pain: a randomized controlled multicenter phase II study

Introduction

A nonblinded parallel-group randomized controlled study investigated the efficacy and tolerability of repeated administration of a bupivacaine lozenge (25 mg) as pain management for oral mucositis pain in head and neck cancer patients as add-on to standard systemic pain management.

Objective

The primary end point was the difference between the intervention group (Lozenge group) and the Control group in daily mean pain scores in the oral cavity or pharynx (whichever was higher).

Method

Fifty patients from 2 hospitals in Denmark were randomized 1:1 to 7 days of treatment with bupivacaine lozenges (taken up to every 2 hours) plus standard pain treatment minus topical lidocaine (Lozenge group) or standard pain treatment including topical lidocaine (Control group). The efficacy analysis included 38 patients, as 12 patients were excluded because of changes in study design and missing data.

Results

Mean pain in the oral cavity or pharynx (whichever was higher) was significantly lower 60 minutes after taking lozenges (35 mm [n = 22]) than for the Control group (51 mm [n = 16]) (difference between groups -16 mm, 95% confidence interval: -26 to -6, P = 0.0032). Pain in the oral cavity was also significantly lower in the Lozenge group (18 mm) vs the Control group (36 mm, P = 0.0002). Pharyngeal mucositis pain did not differ significantly (37 mm [Lozenge group] vs 48 mm [Control group], P = 0.0630). No serious adverse events were reported.

Conclusion

These results show that the bupivacaine lozenge as an add-on to standard pain treatment had a clinically significant pain-relieving effect in patients with oral mucositis.

ClinicalTrialsgov

NCT02252926.

Topical application of morphine for wound healing and analgesia in patients with oral lichen planus: a randomized, double-blind, placebo-controlled study

OBJECTIVE

The objective of this study was to investigate the effect of topical morphine on erosive/ulcerative lesions in patients with oral lichen planus (OLP). Previous studies reported on an enhanced remission of skin wounds when morphine was applied topically.

MATERIALS AND METHODS

This was single-center, prospective, double-blind, placebo-controlled, randomized, multi-arm (3), phase II study (RCT). Patients diagnosed with erosive and/or ulcerative OLP applied 0.2 or 0.4 mg morphine dissolved in glycerine, three times a day for 5 days. The primary outcome was the extent of healing. Secondary outcomes were as follows: (1) effect on pain, (2) presence and severity of opioid-related central and local side effects, (3) whether patients required 'rescue medication' for treatment of pain, and (4) total intake of test substance.

RESULTS

A total of 123 patients were screened for eligibility, 45 patients were recruited into the study, and 43 completed it. Patients applied a solution of either placebo or 0.2 or 0.4% morphine in groups of n = 12, n = 15, and n = 16, respectively. Extent of healing was similar in the three groups. Severity of pain was minor pre-treatment and throughout the course of the study. Only minor adverse events were reported (dry mouth, burning sensation).

CONCLUSION

Morphine did not enhance wound healing compared to placebo-treated patients. Healing was observed in all groups, which may be attributed to an effect of glycerine or to the natural course of the disease. Patients experienced only mild levels of pain, rendering the model insensitive for assessing pain.

CLINICAL RELEVANCE

OLP is a chronic disease and current treatment options are limited. Healing occurred in all three study groups, an effect we attribute to the carrier.

Peripherally applied opioids for postoperative pain: evidence of an analgesic effect? A systematic review and meta-analysis

BACKGROUND

Opioids applied peripherally at the site of surgery may produce postoperative analgesia with few side effects. We performed this systematic review to evaluate the analgesic effect of peripherally applied opioids for acute postoperative pain.

METHODS

We searched PubMed (1966 to June 2013), Embase (1980 to June 2013), and the Cochrane Central Register of Controlled Trials (The Cochrane Library 2013, Issue 6). Randomized controlled trials investigating the postoperative analgesic effect of peripherally applied opioids vs. systemic opioids or placebo, measured by pain intensity scores, consumption of supplemental analgesics and time to first analgesic were included. Trials with sample sizes of fewer than 10 patients per treatment group or trials with opioids administered intra-articularly or as peripheral nerve blocks were excluded.

RESULTS

Data from 26 studies, including 1531 patients and 13 different surgical interventions were included. Clinical heterogeneity of the studies was substantial. Meta-analysis indicated statistically significant, but not clinically relevant, reductions in VAS score at 6-8 h (mean difference -4 mm, 95% CI: -6 to -2) and 12 h postoperatively (mean difference -5 mm, 95% CI: -7 to -3) for peripherally applied opioids vs. placebo and statistically significant increased time to first analgesic (mean difference 153 min, 95% CI: 41-265). When preoperative inflammation was reported (five studies), peripherally applied opioids significantly improved postoperative analgesia.

CONCLUSION

Evidence of a clinically relevant analgesic effect of peripherally applied opioids for acute postoperative pain is lacking. The analgesic effect of peripherally applied opioids may depend on the presence of preoperative inflammation.

Morphine mouthwash for the management of oral mucositis in patients with head and neck cancer

Background:

Oral mucositis is a debilitating side effect of cancer treatment for which there is not much successful treatments at yet. We evaluated the effectiveness of topical morphine compared with a routine mouthwash in managing cancer treatment-induced mucositis.

Materials and Methods:

Thirty head and neck cancer patients with severe mucositis (World Health Organization Grade III or IV) were randomized into the morphine and magic mouthwash groups. Patients received morphine sulfate 2% or magic solution (contained magnesium aluminum hydroxide, viscous lidocaine, and diphenhydramine), 10 ml for every 3 h, six times a day, for 6 days. Both groups received same dietary and oral hygiene instructions and care. Mucositis was graded at baseline and every 3 days after treatment. Patients’ satisfaction and drug effect maintenance were also evaluated.

Results:

Twenty-eight patients (mean age of 49.5 ± 13.2 years, 63.3% female) completed the trial; 15 in the morphine group and 13 in the magic group. There was a decrease in mucositis severity in both of the morphine (P < 0.001) and magic (P = 0.049) groups. However, at the 6^th day, more reduction was observed in mucositis severity in the morphine compared with magic group (P = 0.045). Drug effect maintenance was similar between the two groups, but patients in the morphine group were more satisfied by their treatments than those in the magic group (P = 0.008).

Conclusions:

Topical morphine is more effective and more satisfactory to patients than the magic mouthwash in reducing severity of cancer treatment-induced oral mucositis. More studies with larger sample size and longer follow-up are required in this regard.

Characterization of oral involvement in acute graft-versus-host disease

Acute graft-versus-host-disease (aGVHD) is a major complication of allogeneic hematopoietic stem cell transplantation (HSCT). The purpose of this study was to characterize the oral features associated with aGVHD in patients who underwent HSCT between 1995 and 2010 and developed prominent oral aGVHD. Data was collected from patient medical records and analyzed descriptively. Twenty-one cases were identified, of which 5 (24%) demonstrated only oral features; the remaining 16 had variable involvement of skin (n = 14), liver (n = 7), and gut (n = 5). The median time to onset of any sign of aGVHD was 22 days (range, 8 to 154 days), and that for onset of oral aGVHD was 35 days (range, 11 to 159 days). Sites affected by nonspecific erythema and ulcerations included buccal mucosa (19 of 21; 90%) tongue (18 of 21; 86%; dorsum in 8), labial mucosa (16 of 21; 76%), palatal mucosa (15 of 21; 71%; hard palate in 7), and floor of mouth (7 of 21; 33%). Eight cases (38%) presented with lip ulceration and crusting. In addition to systemic therapies, topical solutions of dexamethasone, tacrolimus, and morphine were used for ancillary support. Oral features of aGVHD may be the initial manifestation and include nonspecific erythema and ulcerations of keratinized and nonkeratinized mucosa and lips. Intensive topical therapies may help reduce symptoms and promote healing.

A randomized, controlled, clinical pilot study assessing the analgesic effect of morphine applied topically onto split-thickness skin wounds

OBJECTIVES

To assess the effect of an opioid administered topically onto a standardized skin wound in patients without significant comorbidity. Findings to date are contradictory, often obtained from multimorbid patients with wounds lacking uniformity.

METHODS

Forty-four patients undergoing surgery for skin grafting were randomly assigned to receive morphine (0.25, 0.75 or 1.25 mg/100 cm(2) wound size) in hydroxyethylcellulose gel or placebo applied onto the excised split-thickness donor wound at the end of surgery. Pain, supplementary systemic opioids and adverse effects were assessed during the first 24 h after application. Healing was examined when the dressings were removed.

KEY FINDINGS

Morphine doses ranged from 0.25 to 5.4 mg (mean 1.93 ± standard deviation 1.34 mg). No differences in pain scores or use of supplementary analgesics were found between the groups. Serious adverse effects did not occur; healing was not impaired. Large intragroup variability was observed for pain scores, wound sizes and supplementary analgesia.

CONCLUSIONS

Patients treated with topically applied morphine gel onto standardized skin wounds did not report lower pain scores compared with placebo-treated patients. Larger groups would be required to arrive at definitive conclusions. The split-thickness skin graft model can be used for future research.

Endogenous opiates and behavior: 2012

This paper is the thirty-fifth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2012 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).