Everyone must use steroid eye drops after the operation. These are necessary to ensure that your eye doesn't get too inflamed, which would cause you pain and might damage the graft. They are also the most important protection against rejection. Steroid drops can have side effects, which must be watched for. They can cause pressure rises inside the eye, they reduce resistance to infection and, with very prolonged use, can cause cataracts. Therefore it is very important that you are examined regularly to monitor the treatment, and that you report promptly to your doctor if you think you have a problem. The steroid drops are slowly reduced in strength and frequency and are usually stopped between three and six months after the operation, although some people may need to use them for longer.