Nortriptyline
"I apparently have tension headaches rather than migraines,  I had headaches about twice a week for maybe 9 years.  They last up to 16 hours and usual medications usually did very little.  Started 10mg Nortriptyline, worked immediately, but faded.  Took it up to 20mg, same thing.  Went to 30mg., and it lasted a while, but then faded.  For about 7 months I only had about 2 headaches a month.  So I stopped taking it.  After a few months, started getting 4 or 5 headaches a week for the past 2 months.  Got back on Nortrip about 10 days ago at only 10mg.  No headaches until yesterday.  So as of last night I took it up to 20mg.  I didn't want to go past 30mg but may have to.  Vivid dreams that sometimes wake me, dry mouth are my side effects."