Is it true that haveing sciatica can effect bowel and bladder control?

Sciatica: Having a problem with the lower lumbar and sacral nerves can cause "cauda equina" syndrome. This can effect bowel and bladder. These nerve levels join to make up the sciatic nerve. Therefore you can have problems with both.

Yes: Rarely, in about 1% of cases of disc herniations, bowel and bladder control can be impaired. This is known as a cauda equina syndrome and is a reason to be seen emergently as it can lead to pemanent problems if left untreated which is usually surgery if due to nerve compression.

Cauda Equina: Inability to urinate is an emergency. I would make sure you don't have what is called cauda equina syndrome. Unfortunately this requires surgery to correct. Ofetn times the nerves are just bruised abit and the signals aren't being sent quick enough, you may need an epidural steroid injection to relieve this irritation. Either way, i would see a pain/spine specialist to evaluate your options

Yes: If you are having bowel and bladder control you need to see a doctor asap.

Sciatica: Yes. It is rare but when there is a very large ruptured disc that compresses not only the nerve root (sciatica) but also the spinal sac where the nerve roots travel (cauda equina or horses tail) there can be loss of bowel function and an inability to urinate. The legs will be weak and numb too. This requires urgent neurosurgical decompression to restore function.