Hi , I'm James DVM MRCVS and would like to help you with your question
first let me start by saying that most dogs are very nervous when traveling , this is for them an unnatural feeling which unsettles them and make them as well act unexpectedly ( Rino might be barking at other cars as he is frightened from this objects that are moving towards him and he is unable to avoid).
As Rino is indeed a nervous dog when it comes to traveling this poses a problem. There are drugs which you can give that can calm him down - most commonly used are Acepromazine tablets , which can work but as well may not and would require a large dose in order to keep and extras stressed dog calm but would as well keep him rather sedated after the ride is over .
The question you need to ask yourself - is it necessary to have Rino with you where ever you go in your car or would it be possible to keep him home as he is otherwise a good boy by my understanding.
Having a dogs that does not like traveling in the car - on regular trips is not healthy for the dog on a long term base (with you of sedating drugs or without) as well as dangerous for the driver.
My advice would be to let Rino chill at home if possible or find an alternative solution which would allow him to avoid traveling by car .
I hope this helps .
If you have any further questions - please let me know and I would be happy to help.
all the best .
I would not be having Rino in the car often but as I live in a very rural area if I am going away and need to take him to kennels perhaps overnight, I have to travel at least 2hrs. Or if a visit to the vet is required the same applies. Where can I get the Acepromazine tablets. Can I get them online.
No. These are prescribed drugs. Only your Vet can give them