The foreskin of the penis cannot be pulled back from around the tip of the penis is called Phimosis.Phimosis occurs naturally and it is common in boys who are uncircumcised. Also occurs due to infection which scars the foreskin or if the foreskin is forcefully moved and it may be triggered by hormonal imbalance or abnormal immune response.The symptoms include the inability to retract the foreskin accompanied by redness, pain or swelling.