Passiflora / Passionflower
Wow, I don’t believe it, passiflora incarnata has only ever been mentioned once before me on this forum (by @dee_B, 2013), altho I think most of us suffer from sleep problems. It was actually the first substance suggested to me for sleep, by my first psychiatrist. It didn’t help when I tried it first, but now I’ve been taking it with GABA and (at first) glutamic acid again since starting with GABA April 15th and getting lots of improvements.
OK, I’m putting a focus on it now, as it seems that removing magnesium glycinate and doubling passiflora from 2x289mg to 4x has greatly improved my sleep depth, intensity, stints, breaks & effectiveness. Removing magnesium malate now too, I want to see how much higher I might dose the passiflora, as 4x is the max. it says on the lable.
Dosage varies greatly from 90 to 900mg per dose, no real recommendations, however with the 4 capsules I'm taking and recommended on my lable I'm already at 1,156mg
Webmd: Passion flower extract products typically provide 250-900 mg per dose. But there isn’t enough reliable information to know what an appropriate dose of passion flower might be.
Verywellmind: 500 mg of passiflora incarnata 90 minutes prior to surgery
drugs: 90mg or 500mg
While I’m at it, this study from 2010/2011 says it seems good for “anxiety or nervousness, Generalized Anxiety Disorder (GAD), symptoms of opiate withdrawal, insomnia, neuralgia, convulsion, spasmodic asthma, ADHD, palpitations, cardiac rhythm abnormalities, hypertension, sexual dysfunction and menopause”
and seems to work via modulation of the GABA system including affinity to GABA(A) and GABA(B) receptors, and effects on GABA uptake. In rats at least. (grrr 
I love them.)
Also another study from 2011/2012 says it improves “PTZ-induced seizures, and ameliorates its associated post-ictal depression”.