Table 2

Observational studies of gabapentinoids

Study	Year	Setting/design	Inclusion criteria	Patient number	Age (years)	Intervention groups	Dosing regimen	Outcomes	Follow-up
Kneib et al26	2019	Single center retrospective cohort study	Admitted to burn unit, complained of itch	411	>14	Use of neuropathic pain protocol. Analyzed by group: Gabapentin at <72 hours Gabapentin >72 hours No gabapentin	Gabapentin 300 mg once daily increased every 2 days if NRS≥5 to max 900 mg three times a day	Morphine equivalent dose Total gabapentin use Pain and itch NRS Short Form-12 survey	24 months
Nieuwendijk et al28	2018	Single center prospective observational study	In burn ward or outpatient clinic, complained of itch	413	<13	Not protocolized. Mixture of no treatment, gabapentin, and antihistamine	Gabapentin 5 mg/kg	Itch Man Scale 0 to 4 Itch NRS (0 to 10)	1 week to 3 months
Kaul et al25	2018	Single center retrospective observational study	Pruritus or neuropathic pain on gabapentinoid	136	0 to 20	Gabapentin only or in combination with pregabalin	Various gabapentin doses used from 50 mg three times a day to 1200 mg three times a day. Pregabalin 50 mg to 100 mg three times a day added if inadequate response to gabapentin.	Retrospective review to describe effective dose of drugs	Unclear
Zachariah et al11	2012	Single center prospective observational study	Burn 6 weeks to 2 years old, pruritus with failure of cetirizine and emollients	23	4 to 60	Gabapentin added if cetirizine inadequate	Adults—gabapentin 100 mg twice daily, increased to max 300 mg three times a day Children—5 mg/kg twice daily to max 5 mg/kg three times a day	Itch severity scale (7 to 21 points)	6 months
Goutos et al14	2010	Single center prospective observational study	Within 72 hours of injury, admitted to burn unit, sense of itch and urge to scratch	91	Adults and children	Two consecutive protocols. Gabapentin introduced early or late, compared with pre-protocol data.	Adult 300 mg once daily titrated to 300 mg three times a day over 3 days Children 5 mg/kg once daily titrated to 5 mg/kg three times a day over 3 days	Itch Man Scale 0 to 4	Unclear. Only inpatient data.
Mendham et al27	2004	Single center prospective observational study	Itching burn wound, admitted to burns unit	35	Children	Gabapentin (no comparator or control)	5 mg/kg three times a day to max 5 mg/kg twice daily plus 10 mg/kg nocte	Staff or parent reporting of itch reduction	Unclear. Some followed up for 18 months.

NRS, Numeric Rating Scale.