BERLIN—Russian opposition leader Alexei Navalny has been discharged from the hospital after being treated for what scientists said was exposure to the military grade nerve agent Novichok, Berlin’s Charité Hospital said Wednesday.

He was discharged Tuesday night after 24 days in intensive-care unit, the hospital said. He had been receiving treatment in the German capital since late August after falling ill while traveling in Russia.

The hospital said while doctors believed Mr. Navalny could achieve a complete recovery, it was too early to say if he would suffer long term effects from the poisoning.

Write to Bertrand Benoit at [email protected]