I read that in many cases boenninghausen prescribed 2 or 3 remedies simultaneously.The remedies were given at particular intervals.Most of the present homeopaths advocate use of only one remedy at a time.
According to the Heilkunst homeopathic practitioners, two different diseases may exist in the body at the same time and so two remedies may be able to work at approximately the same time. Practicing at this level requires a thorough understanding of the process and years of experience.
Unless you are an experienced Heilkunst practitioner, you should use ONE remedy at a time.
Alan V. Schmukler