Illness

It's not always easy to detect when your cat is unwell. Cats are very good at hiding illnesses, and tend to shy away from contact if they're feeling under the weather. It's important to keep an eye open for the telltale signs of common conditions, and a good idea to complete a monthly health checklist at home. If you do notice anything out of the ordinary, don't rely on books or websites for a diagnosis. Contact your vet immediately. What to look out for;

General lethargy, tiredness - just looking unwell
If for any reason your cat isn't his or her normal, healthy, active self, it's worth taking a closer look. Like humans, cats can just look unwell, and even if there are no obvious clues to what’s wrong, a trip to the vet is a good idea if this persists. Eyes should be bright and clear, without runniness or redness. Your cat should not shy away from light; ears should be clear of thick dark wax; nostrils free of discharge.
Repeated vomiting, gagging or sickness
Occasionally vomiting hairballs or grass is quite normal. But persistent sickness or choking when eating is a concern. Vomiting can be a sign of illness, such as kidney disease, particularly in older cats.
Refusal to eat for over 24 hours
If your cat spends a lot of time outdoors, eating patterns may occasionally become irregular. But if your cat refuses food for a day or more consult your vet.
Diarrhoea
If your cat has persistent diarrhoea that lasts for longer than 48 hours, visit your vet. If possible, take a stool sample with you. Mucus in stools also indicates intestinal problems.
Difficulty urinating
Look out for behavioural signs similar to constipation, crying when urinating or blood in the urine. Feline Lower Urinary Tract Disease is a common condition, particularly for males, and can become life threatening if not treated early.
Progressive weight loss
You should be concerned if your cat appears to lose weight progressively over two to four weeks, or shows a slow but steady weight loss over a longer period.
Progressive weight gain
Watch out for signs of excessive weight gain and obesity, which can lead to diabetes, mobility problems and other diseases. You should be able to just feel your cat’s ribs. Obesity can require a vet’s help to treat. Excessive weight can be controlled by gradually reducing your cat’s food until it’s normal weight is reached.
Excessive thirst or urination
Unusually excessive thirst and frequent urination can be a sign of feline diabetes, as well as other medical conditions.
Itchy, flaking skin
Skin condition is a good general indicator of health. Skin should be smooth, and pink or black. Persistent itching and signs of dermatitis could indicate an allergic reaction, particularly to fleabites.
Red or swollen gums
Reddened or swollen gums, particularly when associated with bad breath, are an indication of gum disease. When severe, cats may lose teeth, drop food from their mouths and suffer weight loss due to the difficulty of eating.
Runny eyes or nose
Sneezing, panting, runny eyes and nose or other flu-like symptoms may be signs of respiratory problems, as are gasping or shortness of breath.