How to Keep my German Sheperd Mix with Labrador dog calm in a long car ride

[Sofia_123]

When my and my dog and 2 children are in the way for my dog to get her shots alond the way she starts vomiting all over the car.  My dog starts wining and barking.  Could you tell what to do cause i am tired of all the vomiting.

[Artmaker]

OH been there as well.   I have two sisters, lab mixes.  One was fine but the other puked up the car every time.  I started using a crate simply because it was easier to clean the inevitable mess.  But it also helped keep her calm. Probably because she couldn't jump around as much but maybe because she had less view of the world flying by too.  
The vet told me you can actually give a dog dramamine before a trip but check with your vet first as the dose has to be right for the size of your dog.
And like Margot49 already pointed out, frequent short trips really do help.

Fortunately she outgrew this puking phase.  They are 12 now and both are perfect travelers even on the longest trips.  

[Margot49]

Oh, been there!  What kind of dog and is she in a crate?  Is she loose in the car or can you at least confine her to an area?  If you have a trip planned, don't feed her at all or very much.  You can try giving a couple of Ginger Snap cookies about an hour or so before you go.  Ginger helps settle the stomach.  U.S. she used to the car?  This could be a combination of upset stomach and nerves.  Have you tried conditioning her to the car by just making short, frequent trips around town.  I think we had a past thread on this. You might try a search.  You can cover the area she is in with old tiweks or news paper.  You can also get a baby bib and put it on her in the car.