Here's what rhymes with synaptogenic.
antigenic pyogenic pathogenic splenic biogenic eugenic phrenic teratogenic androgenic allergenic photogenic irenic telegenic transgenic cryogenic iatrogenic mutagenic neurogenic hypoallergenic anthropogenic psychogenic schizophrenic carcinogenic neurasthenic calisthenic hallucinogenic callisthenic Words that almost rhyme with synaptogenic
epidemic polemic pandemic totemic pfennig academic endemic systemic epistemic ischemic leukaemic nonacademic technic benthic derrick genetic poetic authentic generic acetic diabetic pathetic pelvic angelic ascetic ferric relic peptic allelic eutectic steric dietetic geodesic geodetic medic fetich pectic domestic energetic kinetic prophetic athletic majestic metric esoteric forensic phonetic septic alphabetic apathetic aseptic centric cleric enteric hectic emetic sceptic tartaric turmeric hermetic acerbic antithetic lovesick paregoric bathetic magnetic aesthetic sympathetic atmospheric dialectic geometric symmetric antiseptic apologetic cosmetic epileptic esthetic numeric diuretic obstetric prosthetic empathetic frenetic isomeric psychedelic skeptic apoplectic chimeric dyspeptic hysteric peripatetic antipathetic evangelic paramedic paraplegic polytechnic pyrotechnic diametric gametic parenthetic redbrick unauthentic electric synthetic anesthetic dielectric eccentric asymmetric concentric eclectic mesenteric parametric anaesthetic isometric phylogenetic barometric cybernetic monomeric ontogenetic photometric anorexic dyslexic geocentric inauthentic anorectic homiletic splenetic unaesthetic unapologetic exegetic copacetic phrenetic dyslectic arithmetic econometric unsympathetic antidiuretic egocentric ferromagnetic geomagnetic kinesthetic alphanumeric ionospheric cataleptic thermometric narcoleptic telekinetic nonathletic psychokinetic unesthetic volumetric psychometric biosynthetic colorimetric ethnocentric neuroleptic paramagnetic anthropocentric heliocentric radiometric nonmagnetic onomatopoetic nonelectric cliometric parasympathetic photoelectric photosynthetic isoelectric nonparametric piezoelectric stoichiometric trigonometric electromagnetic hydroelectric pharmacokinetic