What kind of alkali do you need to cure a bee sting?

Bee venom is a complex substance and, although it is acidic, it is not its acidity that causes the pain and swelling. These are caused by other components, mainly by the peptides apamin, which is a mild neurotoxin, and melittin, which damages the surrounding cells. Remember that the venom has been injected under the surface of the skin and deep into the tissues, so any chemical applied to the surface of the skin that is strong enough to have any neutralizing effect will probably do more harm than good.

There are many household remedies for bee stings, but it is doubtful if any of them have any real effect. Most probably rely on the placebo effect.