Opium seems more likely, and Santa Anna "married" (sham ceremony, and he already had a wife) a pretty local girl. After the post-nuptial night, he sent her to Mexico "for his old age". This is from, "The Alamo", by the late Lon Tinkle, which researched an enormous amount of records,both Texan and Mexican. This book originally was called, "Thirteen Days to Glory". It has an extensive biliography.
Many libraries should have it.

Some posts in this thread have been inaccurate, and I suggest readng this or a similar book to get the straight facts.

T-Star