Hi Snake,
For regular spinal breathing pranayama practice, I use nose breathing.
As a sometimes starter option, used as a priming breath to sensitize the spine(sushumna) and stimulate the energies within it, one can begin a spinal breathing session with a breath that combines breathing through both the mouth and nose together. For a couple of breaths (inhalation and exhalation) both up and down the spine one simultaneously breathes in through both the mouth and nose without kechari.
During the inhalation an aspirated HAH sound is made by the breath while feeling the cool current ascending. On the exhalation an aspirated HEE sound is made by the breath while feeling the warm current descending. Care should be taken to perform it properly. An indication that it is being done so is that it will engage and help open up the full range of the throat, both the upper portion of the throat and nasal area (from the nose breathing) and the lower and deeper part of the throat (down through the larnyx, vocal cords) through the mouth breathing. There is a very open physical sensation in that area which is unmistakable.
It is a somewhat coarser practice than standalone nose-breathing but when used as a starter-primer for a few breaths can help to open up the full range of the throat and medulla oblongata and get the energies flowing in the spine-sushumna. After a couple of breaths in this fashion, one can then switch back to normal AYP spinal breathing through the nose (with kechari if you are using).
Hi Sparkle,
For those that have sinus problems that neti has not corrected, one natural over the counter product, a nose spray called XClear has helped some. It is a saline solution that contains xylitol. The bacteria feed on the xylitol. The xylitol particle is too big for the bacteria to digest so they basically eat themselves into extinction. It has helped some folks where a simple saline solution did not.
There is also another product carried in health stores called Advantage Sinus Aid. Distributed by Wisdom of the Ages, it is a saline solution that also contains Advantage Liquid Concentrate (ie. ALC) an anti-bacterial, anti-fungal, anti-viral solution that contains grapefruit seed extract, green tea extract and jasmine tree extract. My fiance who teaches kindergarten and has had sinus difficulties, uses both of the products I described during flu season when alot of her children are sick to help keep healthy herself and they have proved very helpful.
Love and Light,
Steve