Why does Anne Frank take Valerian pills every day?

In 1942 the Nazis were cracking down on the Jewish people who lived in Germany and other countries.  The Frank family went into hiding so they could avoid being split up and sent to concentration camps.  Anne Frank kept a diary of her experiences.  As the time passed and the annex where they lived became more crowded it was very important for the families to be extremely quiet and not do anything to be detected.  If found, it would not only put them at risk but also endanger the family that was hiding them. 

For the most part Anne was a precious child who was bubbly, friendly, and  sweet.  As time went on, and the confinement streched out before them, Anne began to suffer from depression.  As the depression continued she began taking Valerian pills for the anxiety and depression. 

In October of 1943 Anne wrote:

"Outside, you don't hear a single bird, and a deathly, oppressive silence hangs over the house and clings to me as if it were going to drag me into the deepest regions of the underworld.... I wander from room to room, climb up and down the stairs and feel like a songbird whose wings have been ripped off and who keeps hurling itself against the bars of its dark cage."

Even her family tried to help with this situation.  Anne writes that the family began "plying me with dextrose, cod-liver oil, brewer's yeast and calcium."