Wow thats awesome that you chose to rescue a dog in need and not buy one! Thanks for your contribution to helping homeless pets or those in need.

Yes, Worming can take more then one dose. Hopefully you got the medication from your veterinarian. The way I've noticed the vets I work with do it is they give a heavy dose of medication one day and repeat in two weeks. They can come out for days but if you are worried talk to your vet.

Iams is a great dog food you may want to buy one specially made for coat and skin improvement. You can also buy Omega-3 capsules from your vet or pet store that will help improve the skin and coat quicker.

You can bathe as often as every two weeks but make sure it is with a gentle cleanser maybe an oatmeal based shampoo. You dont want to take away too many of the natural oils from your new pet's skin which could cause drying if given a bath too much. Again you may want to consult your Veterinarian about this.

Shih Tzu is a breed that usually requires regular grooming. You might want to get his hair cut if you have not already just to get all the dead nasty hair off. Depending on how fast his hair grows and how much you brush him will determine how often he needs this done.

Dont forget to make sure he is up to date on all his vaccines and heart worm prevention since he was covered in fleas make sure he stays on flea prevention such as Advantage, Advantix or Frontline, Revolution is a flea and heartworm prevention all in one but can be pricey. I'm not sure if he is neutered or not but getting that done can prevent problems later in his life.

Good luck with your new addition I'm sure he will bring you lots of joy. Plus, seeing how much he improves will be a great reward for you!
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3 years expierence in the veterinary field

Iams is not the best dog food, There is a food call Eagle Pack Holistic Foods. When I rescued my poodle he had half his fur missing and within a month of eating this food his fur was growing back in nicely and his skin improved dramatically from the dry flaking it was. I used the kind in the gold packaging. I would bathe him about 3 weeks to a month (depending on smell) and use Hartz Infusions Moisturizing Vitamin Shampoo. It works wonders on my dogs.
I am not sure about the worms check with your vet. I am hoping you cut all of the mats out of his fur already too. Those can be very painful for the dog. You are wonderful for rescuing him.
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Bless you for taking him! There should be no such thing as an "outdoor" shih tzu! They don't tolerate heat OR cold well. These dogs are bred to be companion dogs (lap dogs).
I've never rescued a dog that had worms THAT badly, but my vet says it does take two doses on very rare occasions.
As far as the deplorable condition of his skin and coat goes, take him to a groomer and have him clipped in a "puppy" cut. That will get rid of all the mats and smells. Get them to do a flea dip while he's there. With regular brushing and bathing, by the time the coat grows back he should be a beauty! Especially because he is getting better nutrition now, too. I'm amazed the poor little guy doesn't have "hot spots" on top of everything else!
Shih tzus are sweet, adorable little snuggle bugs. He'll be SO grateful that he gets to live with you that you will have a friend and protector for his whole life!
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if his coat is really bad have clipped really closely i,m sure your vet will agree it doesn,t take too long to grow back but while its really short you can bath him properly and eradicate the parasites (flees,ticks and whatever else you find) don,t overdo the worm treatment or you will upset his stomach leave that to the vet the vets medication is far better than anything sold in a pet shop as for his coat smell when its grown back have a word with people that sow your breed of dog i used to show dobermans and we used to buy a spray to make their coat shine and it smelled really lovelly well you won,t want to make his coat shine but shih tzu breeders and showers probably use something similar
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Your comment he's been on worm med for days..concerns me…what worm medicine? and did you get it from the vet? The over the counter meds should not be give daily. PLEASE make sure you are giving him the correct dose and not giving him too much. If it was Panacure that is a prescription wormer that is given for a few days..the vet would give you a packet of powder for each day. If he has that many worms he should have a vet check after the first worming and a fecal check should be done to see if there are still worms. Good food will help him with everything. If he is matted you should take him to a groomer so they can flea bathe him after they shave the mats off. Then you can bathe him every 4 wks…more can lead to dry, flakey skin..oatmeal shampoo and conditioner are good for Shih Tzus and he should be taken to the groomer every 4-8wks to keep his coat at a good length. The groomer will also clean his ears and trim his nails.
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Boarding, grooming, show and breeding kennel owner for over 12yrs