Elavil, Endep, Vanatrip (amitriptyline)
Tricyclic antidepressants (TCAs), such as amitriptyline, are linked to weight gain more than other antidepressants or migraine meds.
TCAs affect neurotransmitters involved in energy and appetite, such as serotonin, dopamine, and acetylcholine, but their antihistamine activity is probably the reason for weight changes, Roerig says.