Table 2:

Summary of available evidence of commonly used medications for GP (Only results from randomized controlled trials are summarized)

Medication	Mechanism of Action	Available Evidence in Adults	Available Evidence in Children
Erythromycin	Motilin receptor agonist	- SR* (2003)[59] - SA* (1999)[58] - DB*, PC*, XO* – improved antroduodenal motor activity (1997)[55] - RC*, DB, PC – accelerated gastric emptying (1995)[56] - OL* (1994)[60] - OL (1994)[61] - OL (1993)[63] - RC, DB, XO with metoclopramide – improved symptoms, more pronounced with erythromycin (1993)[62] - RC, DB, PC, XO – accelerated gastric emptying (1990)[57]	- Re (2012)[14] - SR (in neonates) (2005)[73] - RC, DB, PC – no difference (2003)[70] - RC, DB, PC – no difference (2003)[71] - RC, DB, vs metoclopramide study (2001)[64] - RC, DB, PC – accelerated gastric emptying (2001)[68] - P, RC, DB, PC – improved enteral feeding (2001)[69] - RC, DB, PC – improved gastric emptying (2001)[72] - RC, DB, PC – no difference (2000)[66] - RC, DB – no difference (1998)[67]
Metoclopramide	Dopamine D2 receptor antagonist, serotonin 5-HT4 agonist	- MA*, SR (2019)[80] - RC, DB, PC – reduction in GP symptoms in women but not men (2015)[82] - RC, DB, vs domperidone – equally effective but more pronounced CNS side effects with metoclopramide (1999)[81] - RC, DB, XO with erythromycin – improved symptoms, more pronounced with erythromycin (1993)[62] - RC, DB, PC XO – improved symptoms (1985)[79] - OL (1984)[121] - RC, PC – improved symptoms, accelerated gastric emptying (1983)[78] - RC, DB, PC, XO – improved symptoms and vomiting, acceleration of gastric emptying (1982)[76] - RC, DB, PC – improved symptoms (1979)[77] - OL (1977)[122]	- Re (2015)[75] - Re (2012) [14] - RC, DB, PC – accelerated gastric emptying in infants with regurgitation and infants with GP following abdominal surgery, no change in infants with GP related to prematurity (1988)[83]
Domperidone	Dopamine D2 receptor antagonist but with lower central side effects when compared to metoclopramide	- MA, SR (2019)[80] - RC, PC, vs metoclopramide – equally effective but more pronounced CNS side effects with metoclopramide (1999)[81] - RC, PC, withdrawal study – improved symptoms (1998)[90] - OL (1997)[86] - Re(1990)[87] - OL (1989)[88] - RC, PC, XO – improved symptoms (1989)[91] - OL (1985)[89] - OL (1985)[85] - RC, PC, XO – accelerated gastric emptying (1983)[92] - RC, PC, XO- no difference (1981)[93]	- Re (2012)[14] - RC, PC, XO (2010)[95] - RC, PC vs cisapride – domperidone superior to cisapride in improving symptoms and accelerating gastric emptying (2002) [94]
Cisapride	Serotonin 5HT4 agonist, serotonin 5-HT3 antagonist	- MA, SR (2019)[80] - RC, PC – accelerated gastric emptying (2002)[100] - RC, DB, PC, XO – no difference (1999)[101] - RC, DB, PC, XO – no difference (1999)[102] - RC, DB, PC – accelerated gastric emptying but no improvement in symptoms (1993)[104] - DB, PC – accelerated gastric emptying but no improvement in symptoms (1989)[123] - RC, DB, XO – accelerated gastric emptying but no improvement in symptoms (1987)[103] - RC, vs metoclopramide, PC – accelerated gastric emptying with both, significant with cisapride (1987)[98] - DB, PC, XO – no difference (1987)[99]	- RC, PC, vs cisapride – domperidone superior to cisapride in improving symptoms and accelerating gastric emptying (2002) [94] - RC, PC – improved feeds only in extremely low birth weight infants, but significant QTc prolongation (2005)[106] - RC, PC, XO – no difference (2001)[107] - RC, DB, PC – no difference (2000)[105] - RC, DB, PC – no difference (2000)[108] - RC, DB, PC – delayed gastric emptying (1999)[110] - RC, DB, PC – no difference (1998)[109]
Botulinum Toxin	Decreases pylorus muscle contractility and acetylcholine release	- Re, OL (2014)[124] - Re, OL (2009)[117] - RC, DB – no difference (2008)[115] - RC, DB, XO – no difference (2007)[116] - Re, OL (2005)[125] - P, OL (2002)[114] - P, OL (2002)[113]	- Re, OL (2012)[112]

^*Re= Retrospective, R= Randomized controlled, OL= open label, P= prospective, DB= double-blind, XO= crossover, PC= placebo-controlled, SR= systematic review, SA= systematic analysis, MA= meta-analysis