Alkalis Poisoning in Dogs

Any chemical with a pH above 7 is considered alkali, but compounds registering 11 or above can be very dangerous for dogs and humans. Toxic alkaline ingredients are found in many household products, including cleaning agents, algaecides for the pool, and any type of alkaline battery (either nickel-cadmium or lithium). These chemicals can cause serious corrosive injury through ingestion, inhalation, and dermal contact. Unlike acids, alkaline chemicals don’t cause immediate pain; however they do liquefy the tissue leaving deep burns and ulcerations. Prolonged exposure can lead to more extensive damage making these chemicals even more dangerous than acids.  Symptoms of ulceration and inflammation start to develop within 2-4 hours, but the full extent of the damage may not be evident for up to 12 hours. Extensive burns on the esophagus and stomach are common since toxic alkali chemicals often travel further down the gastrointestinal tract than similar acidic compounds. Skin and eye contact are also extremely dangerous and inhalation of these chemicals can cause perforation of the mucosa and fluid in the lungs. Alkaline batteries can present a special danger since dogs may chew open the battery casing and/or swallow the battery causing obstruction of the gastrointestinal tract as well as alkali burns from leakage. There is no antidote for alkali poisoning. Immediate veterinary treatment is recommended, but in severe cases the damage may still be fatal.

Exposure to strongly alkaline chemicals causes ulceration and deep tissue damage, often with little or no pain upon contact. Dogs are at risk for alkali poisoning from many household products, such as alkaline batteries, some cleaners, and pool chemicals.

These are the signs you may see in a dog with alkali exposure. Symptoms may take anywhere from 2-12 hours to develop.

• Excessive salivation
• Smacking of the lips
• Tongue flicking
• Difficulty swallowing
• Vomiting (with or without blood)
• Abdominal pain
• Blood in the stool (melena)
• Difficulty breathing
• Lethargy
• Ulceration of the mouth, esophagus, or stomach (oral ingestion)
• Coughing and bluish tinge to the skin and mucous membranes (inhalation)
• Squinting, tear production, eye swollen closed (eye exposure)
• Redness and burning at area of contact (dermal exposure)

Types

There are some of the alkali additives that would cause a problem for your dog

• Sodium hydroxide
• Ammonium hydroxide
• Potassium permanganate

Many household products can contain alkalis.

• Drain openers
• Automatic dishwasher detergents
• Alkaline batteries (hearing aids, remotes)
• Toilet bowl cleaners
• Swimming pool additives (algaecides)
• Radiator cleaners
• Bleach
• Hair relaxers

These factors can increase the risk of alkali poisoning.

• Leaking bottles
• Open containers
• Dog chewing through bottle
• Dog chewing and swallowing a battery

If you think you dog has been exposed to a toxic alkali chemical, you should seek immediate veterinary treatment. Bring along an empty or sealed container so the veterinarian can identify the substance exactly. Alkali poisoning will be diagnosed based on a recent exposure as well as burns and ulceration if these symptoms are already present. In most cases, endoscopy is performed with ingestion to evaluate the extent of damage to the esophagus and other parts of the gastrointestinal tract. This involves inserting a small camera down the throat under anesthesia. If the poisoning took place in the last few hours, the extent of the damage may not be evident immediately so the veterinarian may recommend waiting 12 hours. 

Other types of exposure will be assessed with a physical examination. Abnormal breathing sounds may be audible through a stethoscope if there is damage to the lungs and the veterinarian may order a chest x-ray. With ocular exposure, a colored stain may be added to the eye to make corneal damage more visible. Abdominal X-rays could be necessary if your dog has swallowed a battery.

If you don’t have access to immediate veterinary treatment, a poison helpline can be a good first treatment. Your dog will still need to see a veterinarian as soon as possible, however. With alkali poisoning, vomiting should never be induced as this has the potential to cause re-exposure with further esophageal damage. Drinking milk or water can help to dilute the substance and prevent further damage to the esophageal tract.  For skin or eye exposure, decontamination by flushing with cold water is the best immediate treatment. Dogs may not show signs of pain, but prolonged contact will make the condition worse.

For recent poisoning, the veterinarian will keep your dog and evaluate symptoms over at least a 12 hour period. Oxygen may be necessary to manage breathing difficulties, and pain medication and antibiotics will be administered intravenously. If there is severe esophageal damage, a feeding tube may be inserted as your dog will not be able to eat or drink until the burns have healed. Very severe cases can cause the stomach and intestine to rupture which could need to be treated surgically. If the tissue damage is too extensive, the veterinarian may recommend euthanasia. Otherwise your dog will need to stay in a veterinary hospital until he has recovered.

For optical exposure, the veterinarian will flush the affected eye for at least 20 minutes to eliminate all the toxic chemicals. Eye drops will be prescribed to reduce inflammation and limit infection. You may need to apply frequent eye drops if your dog is sent home. If there is severe damage, the veterinarian may recommend an eye specialist. Alkali chemicals in the eye can result in permanent scarring or blindness. With dermal exposure, the veterinarian will thoroughly clean the affected area and prescribe topical ointments as necessary. You may need to change the bandaging and apply creams regularly once your dog is sent home. If your dog has swallowed a battery, emergency surgery could be necessary to remove it, especially if the casing is chewed off and it is leaking.

Dogs may recover from mild alkali poisoning, but prolonged exposure to very toxic chemicals has a guarded prognosis. Immediate treatment has a higher chance of success, but this will depend on the area and severity of exposure. You may need to help your dog adjust to a permanent disability like blindness. Scar tissue in the esophagus could also make swallowing and eating more difficult and further surgery might be needed to widen the esophagus. The veterinarian might also recommend a permanent diet change.

Limiting exposure is the best way to manage alkali poisoning. Store all toxic cleaners, batteries and other alkali products out of reach of your dog. Secure your dog elsewhere whenever these chemicals are in use. Keep pools covered especially when the water is being treated and check regularly for damaged or leaking bottles.