Which of the following therapies may also be helpful to add to her maintenance regimen?

A 70 yo woman with a history of CHF has been taking oxycodone/acetaminophen [Percocet] for some nonspecific shoulder pain. Which of the following therapies may also be helpful to add to her maintenance regimen?

Docusate sodium (Colace)

Senna

Magnesium citrate

Polyethylene glycol (Colyte)