It seemed a routine visit for an upset stomach until I knocked at what turned out to be the penthouse suite of a Beverly Hills hotel. The man who answered identified himself as "the prince's personal assistant." I followed him into another large room where the prince, an elderly Saudi, lay in bed. It was five in the morning.

The assistant indicated the patient - not the prince but a young woman sitting nearby, looking wan. I took her into another room to deliver my care. She was an American in her twenties, and I wondered why she was in the prince's room at this hour. Perhaps she was a prostitute, but she seemed nice.

When I returned to the bedroom, the prince thanked me for coming, adding that he had a personal problem. He suffered crippling back pain and had run out of medication. Could I help? As we talked, I noticed the assistant waggling his finger in a gesture indicating that I should not pursue the matter. I took the hint.

Accompanying me to the elevator, the assistant explained that everyone preferred that the prince's doctor handle the prince's drugs. Then he pulled out a sheaf of bills and paid me far too much. I decline tips except from the very rich.

Most Arabs that I see are ordinary people, but over thirty years the occasional prince turns up. They pay generously and provide material for this column, but so far every experience has been uncomfortable.