Ziconotide-induced psychosis: A case report and literature review

A safety review of approved intrathecal analgesics for chronic pain management

Introduction: Intrathecal (IT) drug therapy is an effective treatment option for patients with chronic pain of malignant or nonmalignant origin, with an established safety profile and fewer adverse effects compared to oral or parenteral pain medications. Morphine (a μ-opioid receptor agonist) and ziconotide (a non-opioid calcium channel antagonist) are the only IT agents approved by the U.S. Food and Drug Administration for the treatment of chronic pain. Although both are considered first-line IT therapies, each drug has unique properties and considerations.Areas Covered: This review will evaluate the pivotal trials that established the use of morphine and ziconotide as first-line IT therapy for patients with chronic pain, as well as safety and efficacy data generated from various retrospective and prospective studies.Expert Opinion: Morphine and ziconotide are effective IT therapies for patients with chronic malignant or nonmalignant pain that is refractory to other interventions. IT ziconotide is recommended as a first-line therapy due to its efficacy and avoidance of many adverse effects commonly associated with opioids. The use of IT morphine is also considered first-line; however, the risks of respiratory depression, withdrawal with drug discontinuation or pump malfunction, and the development of tolerance require careful patient selection and management.

Ziconotide-Induced Oro-lingual Dyskinesia: 3 Cases

Background:

Ziconotide (ZCN), a nonopioid analgesic, is first-line intrathecal therapy for patients with severe chronic pain refractory to other management options. We describe three cases of ZCN-induced movement disorders.

Cases:

Case one is a 64-year-old woman who presented with oro-lingual (OL) dyskinesia with dysesthesias and bilateral upper extremity kinetic tremor. Case two is a 43-year-old man with a 20-month history of ZCN treatment who developed OL dyskinesia with dysesthesias, involuntary left hand and neck movements, hallucinations, dysesthesias on his feet, and gait imbalance. Case three is a 70-year-old man with a 4-month history of ZCN use who developed OL dyskinesia with dysesthesias.

Conclusions:

Intrathecal treatment of pain with ZCN may be complicated by a drug-induced movement disorder where OL dyskinesia is characteristic. The movement disorder is likely to be dose related and reversible with ZCN discontinuation, but a chronic movement disorder is also possible.

Tramadol-associated hallucinations: a systematic review and narrative synthesis of their pathophysiology, diagnosis, and treatment

BACKGROUND

Recent prescribing trends reflect government-led efforts undertaken in both the U.S. and Canada to decrease opioid use. These provisions reflect a reduction in the use of many potent opioids in favour of tramadol. Despite the purported benefits of tramadol over other opioids, little remains known about tramadol-associated hallucinations (TAH).

METHODS

We conducted a systematic literature search in Embase, Medline, Cochrane CENTRAL, CINAHL, PubMed, Scopus, PAHO Virtual Health Library, MedNar, and ClinicalTrials.gov to find reported cases of hallucinations associated with the use of tramadol. For all corresponding cases reporting hallucinations secondary to tramadol use, we extracted data on patient demographics, medical management, and the details on hallucinations. Cases were categorized as "probable TAH" if the evidence supported an association between hallucinations and tramadol use, or "possible TAH" if hallucinations were attributed to tramadol use but the supporting evidence was weak. The "probable TAH" cases were further classified as "isolated TAH" if hallucinations were the primary complaint, or "other existing medical condition" if concurrent signs and symptoms alluded to a diagnosis of an existing medical condition. We then conducted a narrative synthesis of the available literature to contextualize these results.

RESULTS

A total of 941 articles were identified in the initial search. No observational studies or randomized clinical trials were identified with our systematic review; only case reports were found. After a thorough screening, 34 articles comprising 101 patients reported an association between tramadol use and hallucinations. Among these 101 cases, 31 were "probable TAH" and 70 were "possible TAH". Of the 31 cases of "probable TAH", 16 cases were "isolated TAH" while the remaining 15 cases belonged to "other existing medical condition".

CONCLUSIONS

Tramadol-associated hallucinations can result in auditory or visual disturbances, although multisensory symptoms have also been reported. The mechanism underlying TAH remains poorly understood and likely involves numerous receptor types. The relative risk of hallucinations from tramadol compared with other opioids remains unclear.