Let's face it, sometimes dogs get into things they shouldn't. When this happens, it's wise to know what to do, particularly if your dog has swallowed something toxic.
Upon noticing what has or may have been swallowed, contact your veterinarian at once. Depending on what was ingested and time of ingestion, you may be able to make the dog vomit before or instead of seeing the vet; or that may be the wrong approach. If more than an hour has passed since ingestion, if the substance is unknown, is a caustic or petroleum product, is a choking hazard, or the dog is already in distress or is choking, you need to get to an emergency vet clinic immediately. Do not waste time attempting to make your dog vomit at home.
One of the safest ways to induce vomiting in a dog is with hydrogen peroxide. Be sure to purchase the 3% hydrogen peroxide, instead of the higher-strength for hair coloring use. 3% peroxide is widely available, and can be found inexpensively at any pharmacy. Usually it is packaged in a brown bottle to protect the contents from light. The label will say the product is toxic, but it is relatively safe for this purpose.
Another item you may wish to have on hand is an oral syringe. These can be purchased at farm stores, pet supply stores, pharmacies or vet clinics. Visit with your vet about what size to have on hand for your pet. Generally, you want a syringe capable of holding at least 25-30 ml or cc of liquid for a medium-sized dog. Getting foul-tasting liquid down the dog is far easier with a syringe than with a spoon. In a pinch, a turkey baster will work, but you'll need to premeasure the dosage.
Every month or so, test your peroxide for freshness. Put a little in your mouth and swish it around before spitting. If it doesn't fizz, throw it out and replace the bottle. Only fresh peroxide is effective. If your dog is fussy about having his mouth handled, get him used to that now. Smear some peanut butter on your fingers, open his mouth, and rub the peanut butter along his gums. Repeat every few days at random times until he no longer resists. Fill your syringe with chicken broth and 'dose' the dog a few times so he becomes accustomed to the procedure and does not always associate the syringe with foul tastes and an ill feeling. These simple precautions can save valuable time in an emergency.
Keep your hydrogen peroxide and oral syringe, spoon, or turkey baster in an easy-to-find area away from light, and tape a label on the side of the bottle noting the following: date of purchase, and amount to be given. If you have one dog, simply write the correct dose. If you have several, it's best to write the dosage as 'per pound' or 'per kilogram.' General guidelines for weight are as follows: 5 ml's or 5 cc's for each ten pounds of body weight. So, a 50-pound dog would receive 25 cc's. The dose may be repeated up to three times at 20-minute intervals. Some veterinarians recommend a higher dose repeated twice. In a true emergency where time is of the essence and a veterinarian is not readily available, you may need to administer as much as is needed for effectiveness, so have a full bottle on hand at all times.
Visit with your vet about your pet's needs before an emergency arises so you can be prepared. Many feel peroxide works much faster if there is something in the stomach, so recommend offering the dog a bit of dog food to be sure there are sufficient stomach contents to commence vomiting quickly. Others feel that, should the peroxide not work, food in the stomach will only cause the ingested poison to be metabolized faster. Again, discuss this with your vet before the actual need arises.
If you are lucky and your animal is a chowhound, you may be able to administer the peroxide simply by mixing it with a handful of dog food or bread. Most dogs, however, will not willingly drink peroxide; especially if they have experienced it's effects on a previous occasion. You will have to force it down the dog's throat. Tilt the dog's head up, and gently insert the end of the syringe along the teeth inside the lip, and press the plunger while holding the animal's mouth closed. Massage the throat and blow gently on the nose to encourage the dog to swallow. Do not simply open the mouth and squirt it down the throat- while this method is easier, it is also likely to get peroxide down the windpipe. However, in a true emergency, it may be your only option to save the dog, but use it as a last resort. Hopefully, most of the peroxide will be swallowed by the dog. If a large amount ended up on the ground or you, reload the syringe and try again. Try to do this outdoors if possible, as most pets will drool and slobber excessively once the peroxide is administered. Keep the dog outdoors and moving as the peroxide will need to become mixed with the stomach contents to be effective. Vomiting should occur within 15 - 20 minutes. If nothing has happened, repeat the dosage. If the dose has been repeated 2-3 times and/or the substance swallowed was highly toxic and nothing has happened or the dog is worsening, get the dog to a veterinarian instead of waiting for vomiting to occur.
Usually, the dog will vomit within 10 - 15 minutes of hydrogen peroxide administration, so keep him outdoors to avoid messy cleanup. Once it takes effect, deep retching multiple times is to be expected. Stay close to the dog to comfort him, and to prevent him from eating any vomitus or foam. Within several minutes, the animal's heaving should ease, and you should see the entire stomach contents have been emptied. Let the dog rest or move about quietly as he recovers. At this point, if you know that the swallowed item(s) have been safely expelled and pose no further risk, you can start to relax. If the items are not all there, or are highly toxic to begin with, gather up the vomit in a plastic bag and take everything with the dog to the vet. Inducing vomiting may have helped, but your dog may still need additional treatment or monitoring.
Hydrogen peroxide is generally a safe method of inducing vomiting, but it is not foolproof. Some dogs simply will not vomit with its use. Others will fight so strenuously to avoid the dose that it is safer and faster for all involved to go straight to the vet for treatment instead of wasting precious time. A struggling dog may not ingest enough hydrogen peroxide for the method to work and is also likely to inhale the peroxide, which poses a severe risk for aspiration pneumonia. A dog that has inhaled any of the vomited foam may be at risk as well. Watch your dog closely in the hours and days following the incident for any symptoms of respiratory distress, depression, exercise intolerance, or decreased vital signs and seek help immediately. If your pet has a history of aspiration pneumonia or megaesophageal issues, vomiting should never be induced without veterinary supervision.
As a lifelong dog owner and trainer, I've found fresh peroxide to be an integral part of my canine medicine cabinet. While you may never have to use it, the administration of hydrogen peroxide can be a lifesaving method of inducing vomiting in your dog should the need arise.