United Kingdom, Feb. 18 -- Robert Pattinson's therapist asked him if he was on drugs because they "couldn't understand" him.

The 39-year-old actor has recalled how his one and only visit to a therapist backfired as the professional questioned whether he had taken any substances.

In conversation with his The Drama co-star Zendaya for Interview Magazine, Robert said: "I went to therapy once and the therapist asked me if I was on drugs because they couldn't understand what I was talking about. I was like, 'I'm trying my best.'

"I thought I was going somewhere. I got on the boat and I was like... 'I want to get off now.'"

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