Many owners are unaware of what is dangerous to their animals, below is a list of substances which are poisonous to cats and dogs.
Dog Poison Awareness
This can be rapidly fatal in dogs as it causes gastric ulceration and perforation. It should be stored correctly so dogs cannot get loose tablets. It should never be given if you think your pet is in pain, animal medication will need to be prescribed. Signs of poisoning include vomiting and diarrhoea with eventual kidney failure.
Sometimes given as a treat but very dangerous. The higher the cocoa content the more harmful it will be. Smaller dogs will be able to tolerate less than big dogs. Signs of ingestion include fast breathing, panting and nervous excitement.
Grapes, Sultanas, Raisins and Wine
All of these are and can be poisonous. Signs of poisoning include vomiting, diarrhoea, drowsiness and a sore abdomen.
Metaldehyde (Slug Bait)
Dogs find this very tasty so it should be stored safely and dogs should be kept away from areas of the garden which have been treated. It causes violent fits, incoordination, increased heart rate and panting.
Warfarin (Rat Poison)
Dogs also find this tasty so should be kept away from it. Warfarin interferes with the clotting of the blood so dogs will eventually bleed to death. Signs include pale gums, bruising, heamatomas and swollen joints.
Onions, aspirin, weed killers, ant killers and antifreeze (ethylene glycol) are also harmful to dogs.
The Dogs Trust has a very comprehensive list as a pdf.
Cat Poison Awareness
Easily obtainable and very poisonous to cats, just half a 500 mg tablet could cause irreversible damage. Signs of paracetamol poisoning are blue gums, incoordination, facial swelling and depression or excitement.
Many bunches of flowers contain lilies which in just small doses can be fatal to cats. Even when placed up high the pollen still drops so lilies should be avoided. Signs include renal failure, incoordination, lethargy and vomiting.
Fatal to cats in extremely small quantities. It is usually ingested when cats drink from contaminated puddles. Care should be taken when defrosting cars not to spill any. Signs include renal failure, seizures, incoordination and depression.
Household disinfectants, which contain phenols, are ingested by cats by licking them off their paws and coats. They can cause problems such as mouth ulcers, diarrhoea, vomiting and in severe cases convulsions and death.
Metaldehyde (Slug Bait)
Cats find this very palatable and will eat it if it is left within their reach. Therefore it should be safely stored in its original container. Signs of poisoning include incoordination, rapid breathing, blue gums and convulsions.
Alcohol, aspirin, ibuprofen, weed killers and chocolate are also harmful to cats.