Mometasone is a steroid often used to treat seasonal allergies, asthma and nasal polyps. It works by blocking the release of substances that result in inflammation but, like many medications, there are some side effects associated with it. Some mometasone side effects are considered mild — including headaches, a change in menstrual periods and nausea — and do not typically need to be treated. Some patients also notice that their allergy symptoms get worse, or they may start to notice cold or flu symptoms. Some mometasone side effects are considered serious, including skin rash, muscle weakness and asthma symptoms that get worse after using this drug.
It is common for some patients to feel side effects that include headaches, nausea and fatigue. Female patients may notice a change in their menstrual periods, with more severe cramping being one of the most common issues. A hoarse voice and back pain also are mometasone side effects that may occur in some patients. Though these signs are fairly common and usually only slightly bothersome, they should be mentioned to a doctor so a different drug can be prescribed when possible.
Some mometasone side effects include cold or flu symptoms. For example, some patients may notice that their nose is runny or stuffy, and they may have a cough. Nosebleeds, pain in the muscles and joints, and a fever also may occur in some patients. Such mometasone side effects tend to disappear in time, but patients are advised to mention them to their doctor as soon as possible so he or she can keep an eye on these symptoms to ensure that they eventually get better.
While it is common for allergy symptoms to worsen when first using this drug, it is not normal for asthma symptoms to get worse. Patients who begin wheezing or have trouble breathing after taking this medication are advised to see their doctor immediately. Those who notice a skin rash, muscle weakness or numbness anywhere on their body also should see a doctor, because they are likely allergic to this medication. Such patients will be treated and then prescribed a different drug to which they are not allergic. Those who notice a difference in the distribution of body fat also are usually advised to see a doctor, because this is considered a serious mometasone side effect that will not just go away on its own.