MOSCOW — A doctor who saw Russian opposition leader Alexei Navalny in the hospital says he may have been poisoned.

Anastasiya Vasilyeva, who has been Navalny’s physician for several years, said Monday that the swelling and the rash on his face could be consistent with chemical poisoning.

Vasilyeva said hospital officials who previously diagnosed Navalny with an allergic reaction refused to run the necessary tests on him.

Navalny was rushed to the hospital Sunday from a detention facility where he is serving a 30-day sentence for calling an unsanctioned protest. He was arrested several days after a major opposition rally on Saturday that ended with nearly 1,400 people detained.

Navalny ally Leonid Volkov on Sunday complained about “anti-sanitary conditions” at the detention facility, where he had also been detained before.