How to Tell when a Parakeet Is Sick
To tell if a your parakeet is sick, pay attention when you feed it, since not eating or drinking can be a sign that it's ill. Additionally, examine the bird's feathers to see if they are damaged, because some medical conditions cause birds to pluck their feathers out. You can also look for other signs of illness, such as huddling on its perch, puffing up its feathers, or breathing heavily. If your parakeet exhibits these, or any other abnormal behaviors or symptoms, call your vet right away to see if your bird needs medical attention.
Be aware that a parakeet can damage its feathers for a number of reasons. The damage can occur over time or within just a few hours, depending on the cause. Some possible reasons for feather damaging include: Boredom. If the bird doesn't feel mentally stimulated, it will grow bored. Picking at its feathers is a form of distracting itself, much as when a human bites at their fingernails out of boredom or frustration. Diet. If the bird isn't getting a nutrient-balanced diet, it may resort to feather plucking. Stress. A person, pet or habitat could be provoking the bird to feel stressed. Lack of exercise, overly large or small perches, noisy or busy cage location, lack of chewing toys, lack of exercise, etc., can lead to the bird being stressed. You should move the bird to a calm, quiet and low-traffic room. Illness. A medical condition or disease can cause feather plucking or loss such as French Moult. Look for signs of mites. If the feathers are patchy or thin, it may be one sign of mites. Look for other symptoms of mites or other parasites as well. These can include: Crusted or scaly skin around the beak, legs, and eyes. Red lesions on the skin. Restless behavior, especially at night. Clicking noises. Tiny, moving red or black specks in the cage or feathers. Seek advice from your veterinarian. It is important to rule out an illness before assuming the feather-plucking behavior is caused by boredom, diet or stress. Moreover, unless you are an expert, it can be difficult to diagnose a bird's illness. Be alert to any changes in the bird's eating or drinking habits. A failure to eat food or drink water is a very concerning sign, and the bird should be seen by a veterinarian immediately. If your parakeet is lethargic, and won't respond to you calling or offering food, this is a sign of sickness. This may be accompanied by huddling low on its perch, puffing up the feathers or breathing heavily. In addition, the bird may show some of these signs: Weakness Sitting in a corner of the cage or low in the cage Falling off its perch Continuous feather ruffling Failure to preen itself A lack of activity or a strange new posture Walking in circles Having seizures or trembling Sleeping a lot Changes to its singing, or a lack of singing Hanging from the cage by its beak rather than perching. Watch for aggression. A normally placid and happy parakeet may suddenly start to snap at you or behave aggressively if it feels pain or is ill. If the weather or room environment is hot, there is a possibility that the parakeet is too hot. Birds cannot sweat and must use other ways to dissipate heat from their bodies. Signs that your parakeet may be too warm include: Panting (rapid breathing or more breaths per minute than usual)––this is a very serious sign of overheating that needs immediate veterinary attention, first by phone, then by a visit Spreading its wings out Hot feet Flared and red nares (nasal opening) Hot beak Note that these symptoms can also be found if the bird has a fever or respiratory distress, so it's important to seek help from the vet immediately. If the weather or room environment is cold, there is a possibility that the parakeet is too cold. Signs that your parakeet may be too cold include: Fluffing out its feathers Huddling or scrunching over its feet (to keep them warm) Sitting in a corner or finding a hiding spot (possibly to get away from a draft). Check the bird's droppings. Bird droppings consist of a dark solid portion called feces, chalky white urates, and clear urine. Normal droppings should not smell. Any change in color, consistency, or smell is a sign that something may be wrong. If there is a bad odor in the cage, either from urine, droppings or another source, assume that the bird is not well. Green or yellow discoloration may indicate liver disease while black or red may be a sign of internal bleeding. Liquid feces usually indicate diarrhea. Wet feathers around the vent are another sign of diarrhea. Look for discharge. If you see discharge from the nostrils, or crusted areas, the bird is ill. If you notice or feel lumps or swollen parts of the bird's body, this is a problem in need of immediate veterinary attention.  Be alert to any vomiting or regurgitation. This usually signals illness. If regurgitating the budgie may shake its head side to side and expel whole seeds. If vomiting the head will appear wet and may include mucous and seed. Check the parakeet's eyes. If they look sunken, droopy, cloudy or have changed color, these are signs of poor health or an illness. A healthy parakeet will have clear and alert eyes. See the veterinarian first. Use your usual bird-experienced vet to diagnose and treat the bird's illness. You can find an avian vet by using the Association of Avian Veterinarians' database. Follow the vet's home-care instructions with great care. Be prepared to call if you're not sure about anything or if changes occur that worry you. Keep the recovering bird in a warm place that is not too hot. Avoid situating the bird anywhere with drafts, noise or bright light. Keep human and pet traffic to an absolute minimum. Remove distractions from the cage, such as toys, mirrors or bells. Ensure that the bird gets at least 10 to 12 hours of sleep. This may include making the bird's resting area off-bounds to all household members. In some cases, it may help to increase the humidity in your home. Talk to your vet about this; it can assist with improved breathing if the bird is congested, but the vet must okay it first. Keep the fluids up. This can be helped by feeding the bird foods with a high moisture content, such as leafy greens and fruit, provided the vet has said this is okay first. If it is okay to give fruit, float a piece of grape or apple in the bird's water. This can encourage the bird to drink, as well as take the piece of fruit. Ask your vet to suggest a feeding regime. Recovering birds often do well on a diet high in simple carbohydrates because these are easy for the bird to digest. Your bird's vet should give you appropriate suggestions. 
Be aware that a parakeet can damage its feathers for a number of reasons. Look for signs of mites. Seek advice from your veterinarian. Be alert to any changes in the bird's eating or drinking habits. If your parakeet is lethargic, and won't respond to you calling or offering food, this is a sign of sickness. Watch for aggression. If the weather or room environment is hot, there is a possibility that the parakeet is too hot. If the weather or room environment is cold, there is a possibility that the parakeet is too cold. Check the bird's droppings. Look for discharge. If you notice or feel lumps or swollen parts of the bird's body, this is a problem in need of immediate veterinary attention. Be alert to any vomiting or regurgitation. Check the parakeet's eyes. See the veterinarian first. Follow the vet's home-care instructions with great care. Keep the recovering bird in a warm place that is not too hot. Keep the fluids up. Ask your vet to suggest a feeding regime. 