He also has many bumps like cyst
Redness, hair loss, and bumps on your cat's back can be attributed to various factors such as allergies, infections, parasites, or even stress. Since these symptoms have been present for five days but are no longer ongoing, it's wise to continue monitoring the situation closely.
Firstly, check for parasites. Fleas and mites are common culprits of skin irritation in cats. Even if your cat isn't currently on flea and tick prevention, it might be beneficial to start now.
Next, gently clean the affected area with a mild antiseptic solution or wipes specifically designed for cats. This can help prevent any secondary infections from developing.
It's also important to monitor for any changes. Keep an eye on the bumps and redness. If they begin to spread, become more inflamed, or if your cat starts to show signs of discomfort, such as excessive scratching or licking, it could indicate a more serious issue.
If the bumps persist or worsen, or if your cat shows signs of pain or discomfort, it would be best to take him to a vet for a thorough examination and appropriate treatment. Skin issues can sometimes be indicative of underlying health problems that require professional attention.
If you have any further questions, please feel free to ask. Thank you.