As Luella May posted, the oleander is now available in capsule form.
It can indeed be taken for overall health. In European studies conducted in 1986-87 an extract of oleander (nerium oleander extract, or NOE) was found to have six times the immune stimulating activities of the most powerful patented immune stimulators known to man. No doubt that is one of the big reasons oleander is so effective against cancer, HIV, hep-C. diabetes and much more. Along with the fact that it targets unhealthy cells and ONLY unhealthy cells, as well as crosses the blood-brain barrier.
Those who take it as a preventive report more robust health, fewer colds and illnesses, a more healthy appetite (yet conversely a reduced craving for sweets and junk foods). In addition, it either eliminates or greatly relieves virtually every known side effect when used along with chemo, including hair loss. AND, it is virtually unheard of for anyone who takes it as a preventive to ever develop cancer of any kind - and that includes those who have previously had cancer and beaten it.
Side effects are generally mild or non-existent and any that are observed almost always go away in a short period of time, once the amount taken becomes consistent (it is best to start small with the home version and work your way up slowly).
One of my favorite uses for oleander is to further condense the "soup" form until it is the consistency of a sticky syrup and then mix it half and half with a mix of good skin care items (I use aloe gel, vitamin E, tea tree oil and a bit of DMSO and colloidal silver) to make a skin creme that will get rid of just about any kind of skin imperfection - including age spots, warts, moles, pre-cancerous lesions and a variety of other bumps and skin thingies.
A caution is that, besides being extremely toxic in raw form (for those who make their own), oleander extract does cross assay with digoxin/digatalis and so anyone with a heart condition or anyone taking medications for high blood pressure or a heart condition, should proceed with caution and/or consult with a qualified naturopath.