It is extremely important that all new puppy owners be as educated as possible on the health,characteristics and possible defects in their breed. I will try to address these issues here as well as give my opinion on some topics.
My puppies are raised with Royal Canine Baby Puppy Food (dry) as I find they like the small size of the kibbles as well as it being a very good balanced diet. I always keep a dish of food available at all times as it is very important that tiny puppies never go with out a meal to long as this can trigger Hypoglycemia.


HYPOGLYCEMIA (Low Blood Sugar)

Hypoglycemia is low blood sugar and is common in Toy Breeds. Symptoms are a staggered gait,glassy eyes,limpness or rigidity. If left untreated seizures,unconsciousness and finally death. Having NUTRICAL
OR KARO SYRUP on hand and rubbing some on the gums of the mouth will help bring the puppy around
while driving to your vet or animal hospital. Make sure to keep puppy warm but not over heated. Puppies
should be fed small amounts of food at regular times during the day instead of one or two large meals.
These  tiny Chihuahuas should never go with out food for more than 4 hours at any given time when under 6 months of age. 
My first experience with Hypoglycemia was very frightening. Although I read numerous articles and spoke
with many breeders that had experienced it, I was still shocked to find our healthy little singlet playing one
minute and almost dead less than hour later. Had we not been there, she would have died. I found this
happened when mom was weaning her,due to lack of milk and not eating enough food on her own. As soon
as I fed her wet food and separated her so mom could not get to the food first,the problem ended. This puppy
only went Hypoglycemic while she was sleeping. She did not show any signs prior to sleeping as the symptoms usually state. This puppy would play and bounce around full of beans then climb into her little bed with mom to have a nap and that's when she would slip into the start of a coma. It was only by shear fluke that we noticed this. My husband went to check their food and water and was surprised that she did not wake up to play as she always did. He picked her up and she was limp like a puppy that had just died. I immediately put karo syrup on her gums and kept her warm while gently massaging her. About 10 to 15 minutes later, she was back to herself. I have never experienced anything like this before, Thank God I was on the ball and remembered about Hypoglycemia having these symptoms of a sudden crashed puppy and treated it immediately. It is very important to get these puppies to eat as soon as possible when they come around. I suggest having a jar of baby food meat on hand at all times. The sugar will revive them quick, but leaves their system quick also. These puppies need good quality food at all times and I can't stress this enough until they are at least 6 months of age. Please have your puppy checked by your vet if this happens to your puppy as hypoglycemia can be a result of another health problem. 


THE MOLERA/FONTANEL

The Molera is a soft spot on the top of the head similar to a human baby. This is completely normal in the Chihuahua breed and in passed times was considered a sign of purity. The molera can fully close once your puppy
reaches maturity. A molera is NOT a sign of Hydrocephalus.

HYDROCEPHALUS

Hydrocephalus is an excess of CSF fluid on the brain also known as water on the brain. Symptoms of hydro are heads visibly larger than body,lack of growth or un thriftiness, east/west eyes,seizures, balance or gait problems,walking in circles,an inability to learn. Hydro can be confirmed with an ultra sound through the molera at your vet or animal hospital. Puppies with hydro generally do not have long lives. Some vets recommend euthanasia as the human thing to do. Hydro is not curable. Medications can help with less severe to control seizure activity. Shunt surgery is also available for a hefty fee and is not guaranteed to work.

LUXATING PATELLA

Luxating patella is when the (hind leg) knee cap slips out of place. Surgery is available to dogs with severe cases of Luxating Patella with a high success rate allowing them to live a normal life. A Chihuahua should never be allowed or encouraged to jump off a beds,couches,chairs,etc; especially that first year in life when bones are forming. A Luxating Patella is sometimes caused from injury to knee and is not always caused by genetics. It is another reason to keep your puppy on a good diet and keep them from jumping up and down on furniture and stairs.

COLLAPSED TRACHEA

Symptoms include coughing,shortness of breath and exhausted. In severe cases,your pet may pass out from lack of oxygen. Think of the trachea as a straw made of cartilage that carries air from the neck to the chest. When the cartilage collapses, breathing becomes difficult, kind of like sipping soda through a flattened straw. You can treat this condition with medication.

REVERSE SNEEZING

Signs of a reverse sneeze are snorting,honking or wheezing. Over stimulation or excitement can cause your pet to have a Reverse Sneeze. Using a collar or lead instead of a harness when walking your pet may also contribute to this problem.  The best thing to do is to calm your pet down if possible. Calming him might include a cuddle and a nice gentle rub. If that doesn't work, you can try to distract you pet by shaking a tin can that has coins in it or clapping your hands. As a last resort, you can place one finger over both nostrils for a few seconds to encourage him to breath properly from the mouth.

TEACUP,MICRO,MINI,ETC.

The Canadian Kennel Club (CKC) standard does not recognize any of these terms with reference to the Chihuahua. The 'teacup' term is widely used today by people that either want to sell their puppies quickly and for a lot of money or by unsuspecting buyers that just don't know that this is an unacceptable term. The Chihuahua Standard dictates a weight between 2 and 6 pounds. Puppies within this range are acceptable to be shown in the ring. Buyer should be aware that the smaller the dog, the higher the chance of medical issues. there is generally a reason one puppy in a litter of three is only one pound at 4 months old while his siblings two to three pounds at the same age. This does not always mean that the tinier one will not be healthy.

MISCELLANEUOS INFORMATION

Your Chihuahua puppy will bark when there is a knock on the door. However,he can be trained to stop barking with a simple command. A Chihuahua does not bark anymore than other breeds. A Chihuahua should never bite a human hand. There is a fallacy that Toy Dogs are 'ankle biters'. An ankle biter is the sign of a poorly trained pet and this behavior is unacceptable in a 3 pound dog as it is in a 100 pound dog.
Your new puppy should be isolated from other dogs until he is fully inoculated. Pet stores, parks and obedience classes are breeding grounds alone for bacteria, parasites, virus's that can seriously harm or kill a puppy that has not finished his series of vaccines.
Diarrhea is a sign of possible bacteria. If your puppy has diarrhea, take a fecal sample to your vet for testing. This is relatively inexpensive and can save the life of your new puppy.
Make sure you never leave your Chihuahua unattended outdoors. It only takes a small hole in the fence for him to escape. Birds of prey are a HUGE danger to your Chihuahua. Hawks can scoop up a Chihuahua as easily, if not easier than a rabbit.
Pools can drown your puppy. Make sure no water is left that is deep enough for your puppy to fall into.
Never leave your Chihuahua on a couch,chair,or bed. He may want to jump down to see where you have gone. Many Chihuahuas have been known to break their leg or even worse, their backs causing death.
Never ever leave your Chihuahua alone with a young child. Squeezing or dropping a Chihuahua is enough to seriously harm or kill your puppy. Puppies are squirmy and jumpy and can easily flip out of your hands. Best place to play with your puppy is sitting on the floor until they are a bit older.
Never leave your Chihuahua unattended with a larger pet. A Chihuahua can be fearless and not realize the danger in trying to play with a 100 pound dog that is eating or taking a nap.
Chihuahuas can be litter box or pee pad trained. My Chihuahuas do not ever go outdoors in the winter unless they are wrapped up in my coat and have a sweater on and I am taking them for a car ride. A Chihuahua can die from exposure in a few short minutes if left outdoors in cold winter weather. Pee pad training is easy and economical. I know Tisol Pets sells actual dog potty boxes for dogs and I love them. They are easy to clean and made from a light plastic but very durable. They are the perfect size for a pee pad or news paper.
A young Chihuahua should never be left alone for extended periods of time. It is imperative that someone monitors that puppy is eating and drinking properly. Hypoglycemia can happen in such a short time. Arrangement should be made for someone to be home during the first few weeks puppy is at your home. It is always stressful for a puppy when leaving his home and familiar surroundings so it is very important to give your puppy some quite time while he adjusts. Do not handle him to much as he is a baby and needs his rest.  

HOUSEHOLD HAZARDS/DANGERS

Until you see your new puppy close-up for the first time,you absolutely cannot fathom the incredible delicacy and size of a Chihuahua puppy. Pictures do not tell the story. First thing you need to do is puppy proof your home. Like having a human baby in the house,you need to make sure of the safety of your puppy. Make sure the floor is free and clear of small items. Coins,Lego and buttons,even gravel in your entrance can be a hazard.
Teething puppies don't know the difference between a chew toy or electrical cord. A playpen or kennel (ex-pen) can be the safest place for your new puppy to be when you cannot be monitoring him. He will feel safe and secure in the smaller area as well. Placing a blanket, pee pad, food and water in a playpen will ensure a happy,healthy puppy. The den-like atmosphere of a kennel will make your puppy feel at home.
Dogs can't eat everything we do. It is very important that you are aware that certain foods we eat can be toxic to your pet. Examples would be chocolate and raw onions. Please be very cautious when feeding your pet.
Plants both indoor and outdoor can be politeness to your pet. Please find out what kind of plants you have and make sure your pet is safe from this danger. One example would be a poinsettia plant. Most of these plants are poisonous to children and adults also.

GOOD BOOKS I RECOMMEND
There are several good books on the market for caring for you Chihuahua but the one that I find is reasonably priced and well written with lots of information is CHIHUHUAS FOR DUMMIES. This is a great book that I highly recommend. I think all new Chihuahua owners should have.

IMPORTANT INFORMATION REGARDING YOUR NEW PUPPY