The invention relates to a pharmaceutical composition and oral dosage forms comprising a bisphosphonate in combination with an enhancer to promote absorption of the bisphosphonate at the GIT cell lining. The enhancer is a medium chain fatty acid or a medium chain fatty acid derivative having a carbon chain length of from 6 to 20 carbon atoms. Preferably, the solid oral dosage form is a controlled release dosage form such as a delayed release dosage form.