I have an established business selling a product we produce in a certified lab to help people with a severe type of disease, but Google won't let me advertise it there (its the perfect spot, since people are googling for a solution directly). Some people recommended I try Native (Taboola/Outbrain/RevContent).
Business currently runs purely on SEO and word of mouth - people talk about it, link to it, etc, but I know with proper advertising I could blow the roof off this thing.
Any other traffic sources I should be aware of? So far I've only ever used Facebook and Google.
Thanks!
That's a tough one being so specific.
On native very specialized ads tend to get poor ad CTR and wont allow you spend much per day. Native works best for broad & big evergreen verticals.
It's way smaller, but microsoft adcenter for Bing could be worth a shot for search traffic.
Facebook sounds like your best bet overall given their targeting options and look-alike audiences to find your desired customers.
Another option would reaching out to site or email list owners to display your ads.
Buying ad space from site owners and bloggers might be an option too... it's a more complicated route, but if you can find solid sites with decent audiences in your niche, it could work well.
Regarding the email promo that thedudeabides mentioned above, take a look at liveintent to see if they have a related list on offer.
Another option are local directories, search engines or portals ... not sure what GEO you target, but in some countries there are still local SEs that are able to compete with google to some extent and some of them offer KW based ads. There are even national ad networks with KW based targeting in many countries, again depends on the market but for example in my country we have one quite large network that is able to deliver decent volume.
What else is there ...
Classifieds portals are quite big in my area, some of them offer ad space.
You could also try to start an affiliate program or at least get your product listed with some affiliate networks ... it would depend on how niche specific your product is, as the affiliates would still need to find the right traffic for it, so the interest might be low.
You could also try to ride the viral wave a bit, maybe create an ebook addressing the issue and try to spread it with the help of some influencers (with the right FB pages, for example).
The specific nature of your product is the limiting factor here, as thedudeabides already suggested. You need to find the right audience for it, it's a pitty that google wont allow ads for it as that would make everything easier.