Drug abuse is an unregulated sin in Victorian Europe. The availability of drugs is wide, but their circulation is limited by expense. By far the most common drug is opium, imported from the Orient. Heroin and cocaine are also quite available to the wealthy. The Chinese quarters of Liverpool and London are the most common areas in which to find "opium dens', as foreign ghettos often have to cater for vice, since prejudice from native employers makes it difficult to find honest work. Medical science is aware of the detrimental effects of such drugs, but most objections to their use derive from moral, rather than scientific, grounds. Indeed, doctors have a tendency to prescribe laudanum (an opium derivative) as a "magic bullet" which cures all ills.