Dose of Belladonna?

What is the therapeutic dose for belladonna?

I can't give you the therapeutic dose of belladonna. Belladonna, common name Deadly Nightshade, contains alkaloids that are dangerous in an overdose, which is very close to the therapeutic dose. Belladonna is recommended for use by knowledgeable practitioners only. Side effects are dry mouth, difficulty in swallowing, dilation of pupils, heart acceleration, restlessness, hallucinations, disorientation and coma.
Any belladonna available over-the-counter would be homeopathic. Homeopathic remedies are extremely diluted, and are generally regarded as safe, with no side effects.