The society said that too strict rules of the Croatian Health Insurance Authority (HZZO) made those who suffer from this disease often wait too long for drugs.
An estimated 2.3 million people worldwide are hit by this disease and in Croatia this figure stands at 4,000.
Multiple sclerosis (MS) is a demyelinating disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged.
On the occasion of Croatia's national Multiple Sclerosis Day, observed on Monday, the society warned that this disease is the second most prevalent cause of disabilities, ranked second after traffic accidents.