A 25-year-old British male dived into hotel swimming pool in 1989 and sustained a C-6 fracture. Anterior fusion of the cervical spine was performed with a bone graft taken from the right iliac crest. This patient required tracheostomy for clearance of secretions. Neurological examination revealed tetraplegia at C-6 (American Spinal Injury Association Grade A). He has been managing his bladder by an indwelling urethral catheter. The catheter was changed every 4 weeks by a health professional. This patient could not recollect developing autonomic dysreflexia in the past. This patient rang the Spinal Injuries Centre on a Sunday in 2010 and informed the staff that his catheter was blocked. This patient was advised to come to the Spinal Injuries Centre immediately. This patient's brother brought him to the Spinal Unit within half an hour and he was attended to promptly. This patient looked well; he did not have sweating, headache, goose pimples or flushing of the face. He was alert and made the usual conversation about going to his favourite public houses for drinks. He was not breathless. He did not have increased spasms. This patient did not have to wait for any time. This patient's brother lifted him, put him on the bed and undressed him. The blocked catheter was removed. The external urethral meatus was cleaned with chlorhexidine prior to catheterisation. Then this patient, who was lying on the bed, said that the ceiling lights were very bright and glaring. Five milligrams of Nifedipine was given sublingually. This patient started having fits involving his head, face, neck and shoulders with loss of consciousness. A 14-French silicone Foley catheter was inserted per urethra without any delay and 300 ml of clear urine was drained. After this patient received Nifedipine, his blood pressure was 84/51 mmHg. A Venflon was inserted in his foot. Blood tests revealed: haemoglobin, 14.4 g/dl; white cell count, 11.3 × 109/l; urea, 2.5 mmol/l; creatinine, 49 umol/l; glucose, 5.4 mmol/l. This patient recovered consciousness within 5 min. Two hundred forty milligrams of Gentamicin was administered intravenously, as spinal cord injury patients with blocked catheters are susceptible to developing urine infections. This patient recovered well and he was able to take his tea. This patient was admitted to the Spinal Injuries Centre for observation. A request was made for a brain scan for this patient. A blocked catheter and distended bladder led to autonomic dysreflexia and the patient developed convulsions. Computed tomography of the brain would show whether this patient had developed an intracranial bleed as a result of a transient hypertensive episode due to autonomic dysreflexia. CT of the brain revealed no focal cerebral or cerebellar abnormality. There was no intra-cranial haemorrhage. In order to prevent recurrence of autonomic dysreflexia due to a blocked catheter, it was decided to take possible measures to prevent blockage of the urinary catheter. He was advised to drink plenty of fluids. This patient was requested to get his catheter changed more frequently. In case of blockage of the catheter, this patient was instructed to take Nifedipine 5 mg sublingually in order to prevent a rise in blood pressure due to autonomic dysreflexia. This patient was advised to carry Nifedipine capsules with him at all times. His carers were trained how to administer Nifedipine sublingually. At present this patient was taking Oxybutynin 5 mg once a day. After discussing with him, this patient was prescribed 10 mg of modified-release Oxybutynin once a day. He was also prescribed an alpha-adrenoceptor blocking drug, Doxazosin modified-release 4 mg once a day. Doxazosin is likely to reduce the frequency and severity of autonomic dysreflexia. This patient was informed of the side effects of long-term indwelling catheter drainage. For example, long-term indwelling urinary catheters are often associated with problems such as urinary infection, blocked catheters and stones in the bladder. Intermittent catheterisation was preferable to long-term indwelling catheters. Unfortunately, this patient did not have carers who could perform intermittent catheterisations.