Many cocaine misusers are treated by a specialist physician or psychiatrist in drug rehabilitation centres.

BBC: Cocaine

Even in rural parts of the U.S. it can take hours to drive to a specialist, while a primary care physician might quickly email that specialist a photo of, say, a diseased retina first to see whether the trip's really necessary.

NPR: Physical By Smartphone Becoming Real Possibility

Dr. Melina Jampolis, a physician nutrition specialist from San Francisco, California, said losing a pound per week is very reasonable.

CNN: Losing a pound a week, staying positive

"Absolutely these diets must be done under the care of a doctor, " says CNNHealth.com's diet and fitness expert, Dr. Melina Jampolis, a physician nutrition specialist.

CNN: Extreme diets: Life on 800 calories a day