It had been hoped the 25-year-old would be ready to play some part in this week's encounter at Wembley, having recently returned to training, but Pochettino says he is still unclear when Lamela will be ready.
"No, Erik is not on the list," he told a news conference. "He's doing well but still he's not available.
"After one year [out], I cannot say tomorrow, one week or one month. It depends on his evolution."
Midfielder Mousa Dembele could return against the Hammers, though, having missed the last month with an ankle injury.
"Yeah, he's doing well," Pochettino said of the Belgium international. "I need to decide tomorrow [Wednesday].
"It's true different players, when they are injured, you have to assess step by step. But it's good."
Pochettino went on to laugh off questions about captain Hugo Lloris' decision to vote for Zinedine Zidane to win The Best FIFA Men's Coach award.
"He voted for me number two," said Pochettino. "Who number one? Zidane? Well, he's French!
"I am happy, it's normal. Zidane received the trophy for best manager and he deserves to be number one."