The present invention provides compositions comprising water soluble peptides with poor solubility in isotonic solutions which exhibit enhanced bioavailability with reduced adverse effects including injection site reactions. Methods are also disclosed for using such compositions for the treatment of diseases including, but not limited to, cancer, type 2 diabetes, acromegaly, metabolic disorders, endocrine disorders, exocrine tumors, and hormone-related tumors. Methods to reduce adverse injection site reactions and improve bioavailability are also disclosed.