How can homeopathy work if there are no molecules of the original substance left in the medicine?

In truth, nobody knows exactly how homeopathy works, just that it does. Unlike other medicines homeopathy does not work on the material level and there is mounting evidence to suggest that it is a medicine that works with energy in the body. Experiments in the area of quantum physics i.e. at the sub-molecular level, tend to support the theory that homeopathy is like a message to the body to start healing itself.

How do we know homeopathy works? Isn't it just a placebo?

There have been some important trials done in Glasgow which demonstrate that homeopathy isn't simply a placebo. All medicines can behave as a placebo (for some reason coloured ones in particular!) but the experience of homeopaths over the past 200 years is that success rates are too high for the medicine to simply be a placebo. In some cases a lasting and permanent cure is brought about whereas a placebo would only bring about a short-lived, temporary reprieve from symptoms. And the biggest argument against the placebo effect is that babies and animals have been successfully treated many times with homeopathy, and they have no consciousness of what they are being given. Also, just because you don't believe that homeopathy will work for you, it doesn't mean it won't. I have treated total cynics (I used to be one myself!) and it didn't seem to make a bit of difference to how they responded to the remedy, apart from them changing their minds about the placebo effect!

Is there real evidence that homeopathy works?

We as a profession don't deny that more trials are desperately needed into homeopathy. A big research effort is currently taking place at Sheffield University to establish the sort of research model needed to properly investigate it. However there is plenty of clinical and experiential evidence to suggest that homeopathy is effective in treating all manner of symptoms, including mental health problems, hormonal issues, behavioural problems in children and in allergies.