I'm not medically trained but this sounds like overflow diarrhea- when you're constipated and diarrhea flows around the blockage. If the powder is something like movicol it takes awhile to eork and sometimes dose has to be upped - but need to speak to GP. 

Don't use imodium or similar without advice as it will completely stop things up.

He may need further intervention like an enema - again you need to ho back to gp.

Having been in a similar situation fibre made things worse for me

yes him too every 30mins

Hello and thanks for your post. 

Unfortunately, as a nurse led service, we aren't able to offer a medical opinion on your situation. You do need to ask your GP to review your husband, and maybe change some medications. Do tell them about his ongoing constipation problems. They may suggest an enema, or a visit from a district nurse. It is important to drink enough fluids daily to reduce constipation, ideally 2 to 3 litres fluid a day and more in hot weather. So, to take drinks regularly.

The sachets work if lots of fluid are also taken afterwards too. Your husband does need to eat small not large meals regularly. Avoid bran and fibre as this can make it worse, it is better to have fibre from fresh fruit and vegetables. Figs and prunes can help.

Your local pharmacist may be able to suggest non prescription products to try. 

There is some good advice on the NHS Website about constipation

I hope that this reply helps, 

Best wishes,

Vanda