Hi both.
It is possible to be dismissed for being off sick, but it is a tricky subject. The best thing to do is to stay in touch with your employer, and if you are concerned, speak to your local Citizens Advice Bureau. I've been in this situation, and it isn't pleasant. But you are ill, and that isn't your fault - focus on getting better.
The inability of an employee to do a job, for whatever reason, is a valid reason for dismissal. However, the case of the employee who becomes physically or mentally unable to do his or her job because of illness, or is persistently absent from work because of illness, clearly demands special consideration. Tribunals recognise that - especially in the smaller firm - it will often not be possible for the organisation to 'carry' the ill employee, and they understand that a time comes when the employer can no longer be expected to keep open the post of an employee who is off sick.
As with the dismissals for other reasons, however, they expect the employer to have discussed the position with the employee concerned and to be absolutely sure of the facts about the employee's state of health and whether he or she is incapable of doing his or her job, or likely to be persistently absent in the future. This may involve taking medical advice about the employee's condition by talking, with the employee's permission, to his or her doctor. If there is less demanding work available which the sick employee would be capable of doing the tribunal will normally expect the employer to offer it to the employee. Employers should also note that the Disability Discrimination Act Law makes it unlawful for employers with 15 or more employees to discriminate against current or prospective employees with disabilities.
Long winded perhaps, but may assist. CAB are good start if you are really worried.
Good luck
Ken