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Drug Reactions

Most of the time, medicines make our lives better. They reduce aches and pains, fight infections, and control problems such as high blood pressure or diabetes. But medicines can also cause unwanted reactions, such as drug interactions, side effects, and allergies.

What is a drug interaction?

A drug interaction is a change in the way a drug acts in the body when taken with certain other drugs, foods, or supplements or when taken while you have certain medical conditions. Examples include:

Interactions could cause a drug to be more or less effective, cause side effects, or change the way one or both drugs work.

What are side effects?

Side effects are unwanted, usually unpleasant, effects caused by medicines. Most are mild, such as a stomachache, dry mouth, or drowsiness, and go away after you stop taking the medicine. Others can be more serious. Sometimes a drug can interact with a disease that you have and cause a side effect. For example, if you have a heart condition, certain decongestants can cause you to have a rapid heartbeat.

What are drug allergies?

Drug allergies are another type of reaction. They can range from mild to life-threatening. Skin reactions, such as hives and rashes, are the most common type. Anaphylaxis, a serious allergic reaction, is less common.

How can I stay safe when taking medicines?

When you start a new prescription or over-the-counter medicine, make sure you understand how to take it correctly. Know which other medicines, foods, and supplements you need to avoid. Always talk to your health care provider or pharmacist if you have questions about your medicines.

Medicines

Medicines can treat diseases and improve your health. If you are like most people, you need to take medicine at some point in your life. You may need to take medicine every day, or you may only need to take medicine once in a while. Either way, you want to make sure that your medicines are safe, and that they will help you get better. In the United States, the Food and Drug Administration is in charge of ensuring that your prescription and over-the-counter medicines are safe and effective.

There are always risks to taking medicines. It is important to think about these risks before you take a medicine. Even safe medicines can cause unwanted side effects or interactions with food, alcohol, or other medicines you may be taking. Some medicines may not be safe during pregnancy. To reduce the risk of reactions and make sure that you get better, it is important for you to take your medicines correctly. You should also be careful when giving medicines to children, since they can be more vulnerable to the effects of medicines.

Antidepressants

What are antidepressants?

Antidepressants are prescription medicines to treat depression. Depression is more than feeling a little sad or "blue" for a few days. It's a very common, serious medical illness that affects your mood and general mental health It can make you feel tired, hopeless, worried, or fearful. It can change your thinking, sleeping, and eating. Depression may make some people think about ending their lives.

But antidepressants can help many people who have depression. Researchers think antidepressants may help improve the way your brain uses certain chemicals that control mood or stress.

Are antidepressants used for other conditions?

A health care provider may prescribe antidepressants for anxiety, chronic pain, or insomnia. Sometimes providers also prescribe antidepressants for other conditions.

What are the different types of antidepressants?

There are many types of antidepressants. Each one works differently. Providers usually prescribe newer antidepressants first because they don't cause as many side effects as older types. They also seem to help more kinds of depression and anxiety problems.

Most of the newer antidepressants belong to one of these three groups:

If these antidepressants don't help, your provider might suggest one of the older antidepressants. The older types include tricyclic antidepressants (TCAs), tetracyclics, and monoamine oxidase inhibitors (MAOIs). Even though these antidepressants may cause more serious side effects, the benefits may outweigh the risks for some people.

Which type of antidepressant is right for me?

Our bodies and brains all work differently. That means one antidepressant won't work for everyone. You may need to try two or more medicines before you find one that works for you.

Your provider will work with you to choose the best option to try first. You'll consider questions such as:

How long do antidepressants take to work?

Antidepressants usually take 4 to 8 weeks to work, so you'll need to be patient. You may notice that some problems, such as sleeping and eating, get better before your mood improves. That's a good sign. You may just need to give the medicine a little more time to do its job.

Sometimes an antidepressant helps at first, but symptoms return while you're still taking it. But there's usually another one you can try. To get more relief from depression, your provider may suggest combining two antidepressants, using another kind of medicine with an antidepressant, or adding talk therapy or other approaches to improve your mental health.

How long will I need to take an antidepressant?

When an antidepressant starts to work, you and your provider can decide how long you need to stay on it. The typical length of treatment is 6 to 12 months, but some people may stay on antidepressants for much longer.

What are the side effects of antidepressants?

Not everyone has side effects from antidepressants. But if you do have them, they're usually mild and may get better over time as your body gets used to the new medicine.

The most common side effects from antidepressants include:

When thinking about side effects, it's important to remember that there are also risks from not treating depression. Your provider can help you think through the pros and cons of all your options.

If you have any side effects from antidepressants, your provider may suggest ways to manage them while you wait to see if the antidepressant will work. If the side effects bother you too much, you may need to change antidepressants. But you should never change your dose or stop taking an antidepressant on your own.

If you have serious problems or notice any changes that worry you, such as new or worsening symptoms, unusual changes in your mood, or you start acting differently, call your provider right away.

In some cases, children, teenagers, and young adults under 25 may be more likely to think about hurting or killing themselves when starting antidepressants or when the dose is changed. Get medical help right away if this happens.

What can I do to take antidepressants safely?

Antidepressants are generally safe when you use them correctly:

NIH: National Institute of Mental Health

Attention Deficit Hyperactivity Disorder

What is attention deficit hyperactivity disorder (ADHD)?

ADHD is a neurodevelopmental disorder. It is usually first diagnosed in childhood and often lasts into adulthood. But some people don't get diagnosed with ADHD until they are adults. ADHD involves:

What are the types of attention deficit hyperactivity disorder (ADHD)?

There are three types of ADHD:

It's normal to sometimes have trouble paying attention or sitting still, especially for children. But people with ADHD have more severe symptoms that can sometimes cause serious problems, for example, failing grades for a child or a job loss for an adult. The symptoms are ongoing and may affect family and social life, too.

What causes attention deficit hyperactivity disorder (ADHD)?

The exact cause of ADHD is unknown. ADHD probably results from a combination of factors, such as genetics and your environment. Researchers are looking at possible environmental factors that might raise the risk of developing ADHD. These factors include brain injuries, nutrition, and social environments.

What are the symptoms of attention deficit hyperactivity disorder (ADHD)?

The symptoms of ADHD depend on the type of ADHD a person has:

People with symptoms of attention problems may often:

People with symptoms of hyperactivity-impulsivity may often:

People with combined ADHD show a mix of inattention and hyperactivity-impulsivity symptoms

How is attention deficit hyperactivity disorder (ADHD) diagnosed?

There is no single test to diagnose ADHD. One step of the process for diagnosing ADHD involves having a physical exam, including vision tests, hearing tests (for children and adults), and other tests to rule out other problems with symptoms like ADHD. Other problems with similar symptoms include anxiety, depression, sleep problems, and certain types of learning disabilities.

The process also involves a thorough medical history and family history. And it usually includes using standardized ADHD symptom checklists, questionnaires, and/or interview questions. These tools have rating scales (scoring systems) that help the provider see if a person's symptoms and history fit a diagnosis of ADHD.

To make a diagnosis of ADHD, the provider needs to have found all of these things:

What are the treatments for attention deficit hyperactivity disorder (ADHD)?

Although there is no cure for ADHD, treatments may help reduce symptoms and improve functioning. ADHD is commonly treated with:

Good treatment plans will include close monitoring, follow-ups, and making changes, if needed, along the way.

Having a healthy lifestyle, such as healthy eating and regular exercise, may also help manage symptoms.

For school-aged children, school support is important. This could include classroom-based behavioral interventions such as behavior management plans or teaching your child organizational and study skills. It may also include accommodations such as specific seating in the classroom, reduced classwork, or extended time on tests and exams.

NIH: National Institute of Mental Health

Autoimmune Diseases

What are autoimmune diseases?

Your immune system protects you from disease and infection by attacking germs that get into your body, such as viruses and bacteria. Your immune system can tell that the germs aren't part of you, so it destroys them. If you have an autoimmune disease, your immune system attacks the healthy cells of your organs and tissues by mistake.

There are more than 80 types of autoimmune diseases. They can affect almost any part of your body. For example, alopecia areata is an autoimmune disease of the skin that causes hair loss. Autoimmune hepatitis affects the liver. In type 1 diabetes, the immune system attacks the pancreas. And in rheumatoid arthritis, the immune system can attack many parts of the body, including the joints, lungs, and eyes.

What causes autoimmune diseases?

No one is sure why autoimmune diseases happen. But you can't catch them from other people.

Autoimmune diseases do tend to run in families, which means that certain genes may make some people more likely to develop a problem. Viruses, certain chemicals, and other things in the environment may trigger an autoimmune disease if you already have the genes for it.

Who is at risk for autoimmune diseases?

Millions of Americans of all ages have autoimmune diseases. Women develop many types of autoimmune diseases much more often than men. And if you have one autoimmune disease, you are more likely to get another.

What are the symptoms of autoimmune diseases?

The symptoms of an autoimmune disease depend on the part of your body that's affected. Many types of autoimmune diseases cause redness, swelling, heat, and pain, which are the signs and symptoms of inflammation. But other illnesses can cause the same symptoms.

The symptoms of autoimmune diseases can come and go. During a flare-up, your symptoms may get severe for a while. Later on, you may have a remission, which means that your symptoms get better or disappear for a period of time.

How are autoimmune diseases diagnosed?

Doctors often have a hard time diagnosing autoimmune diseases. There's usually not a specific test to show whether you have a certain autoimmune disease. And the symptoms can be confusing. That's because many autoimmune diseases have similar symptoms. And some symptoms, such as muscle aches, are common in many other illnesses. So it can take a long time and some visits to different types of doctors to get a diagnosis.

To help your doctor find out if an autoimmune disease is causing your symptoms,:

What are the treatments for autoimmune diseases?

The treatment depends on the disease. In most cases, the goal of treatment is to suppress (slow down) your immune system, and ease swelling, redness, and pain from inflammation. Your doctor may give you corticosteroids or other medicines to help you feel better. For some diseases, you may need treatment for the rest of your life.

Blood Thinners

What are blood thinners?

Blood thinners are medicines that prevent blood clots from forming. They do not break up clots that you already have. But they can stop those clots from getting bigger. It's important to treat blood clots, because clots in your blood vessels and heart can cause heart attacks, strokes, and blockages.

Who needs blood thinners?

You may need a blood thinner if you have:

What are the different types of blood thinners?

There are different types of blood thinners:

How can I take blood thinners safely?

When you take a blood thinner, follow the directions carefully. Blood thinners may interact with certain foods, medicines, vitamins, and alcohol. Make sure that your health care provider knows all of the medicines and supplements you are using.

You may need regular blood tests to check how well your blood is clotting. It is important to make sure that you're taking enough medicine to prevent clots, but not so much that it causes bleeding.

What are the side effects of blood thinners?

Bleeding is the most common side effect of blood thinners. They can also cause an upset stomach, nausea, and diarrhea.

Other possible side effects can depend on which type of blood thinner that you are taking.

Call your provider if you have any sign of serious bleeding, such as:

Childhood Leukemia

What is leukemia?

Leukemia is a term for cancers of the blood cells. Leukemia starts in blood-forming tissues such as the bone marrow. Your bone marrow makes the cells which will develop into white blood cells, red blood cells, and platelets. Each type of cell has a different job:

When you have leukemia, your bone marrow makes large numbers of abnormal cells. This problem most often happens with white blood cells. These abnormal cells build up in your bone marrow and blood. They crowd out the healthy blood cells and make it hard for your cells and blood to do their work.

What are the types of leukemia in children?

There are different types of leukemia. Some types are acute (fast growing). They usually get worse quickly if they are not treated. Most childhood leukemias are acute:

Other types of leukemia are chronic (slow growing). They usually get worse over a longer period of time. They are rare in children:

There are some other rare types of leukemia in children, including juvenile myelomonocytic leukemia (JMML).

What causes leukemia in children?

Leukemia happens when there are changes in the genetic material (DNA) in bone marrow cells. The cause of these genetic changes is unknown. However, there are certain factors that raise the risk of childhood leukemia.

Who is at risk for leukemia in children?

The factors that raise the risk of childhood leukemia include:

There are other factors that may raise the risk of getting one or more of the specific types of childhood leukemia.

What are the symptoms of leukemia in children?

Some of the symptoms of leukemia may include:

Other leukemia symptoms can be different from type to type. Chronic leukemia may not cause symptoms at first.

How is leukemia in children diagnosed?

Your health care provider may use many tools to diagnose leukemia:

Once there is a diagnosis of leukemia, other tests may be done to see whether the cancer has spread. These include imaging tests and a lumbar puncture, which is a procedure to collect and test cerebrospinal fluid (CSF).

What are the treatments for leukemia in children?

The treatments for leukemia depend on which type it is, how severe the leukemia is, the child's age, and other factors. Possible treatments might include:

Treatment for childhood leukemia is often successful. But the treatments can cause complications right away or later in life. Children who survived leukemia will need follow-up care the rest of their lives to watch for and treat any complications they may have.

NIH: National Cancer Institute

Cholesterol Medicines

What is cholesterol?

Cholesterol is a waxy, fat-like substance that that's found in all the cells in your body. Your body needs some cholesterol to work properly. But if you have too much of it in your blood, it can stick to the walls of your arteries and narrow or even block them. This puts you at risk for coronary artery disease and other heart diseases.

Cholesterol is made by your liver. It travels through the blood on proteins called lipoproteins. One type of lipoprotein, LDL, is sometimes called the "bad" cholesterol. A high LDL level leads to a buildup of cholesterol in your arteries. Another type, HDL, is sometimes called the "good" cholesterol. It carries cholesterol from other parts of your body back to your liver. Then your liver removes the cholesterol from your body.

What are the treatments for high cholesterol?

If you have high cholesterol, lifestyle changes can help you lower your cholesterol levels. But sometimes the lifestyle changes are not enough, and you need to take cholesterol medicines. But you should still continue with the lifestyle changes even though you are taking medicines.

Who needs cholesterol medicines?

Your health care provider may prescribe cholesterol medicines for you if:

What are the different types of cholesterol medicines?

There are several types of cholesterol-lowering drugs available, including:

There are also a few other cholesterol medicines (lomitapide and mipomersen) that are only for people who have FH.

How does my health care provider decide which cholesterol medicine I should take?

When deciding which medicine you should take and which dose you need, your provider will consider:

Medicines can help control your cholesterol, but they don't cure it. You need to keep taking your medicines and get regular cholesterol checks to make sure that your cholesterol levels are in a healthy range.

Epilepsy

Epilepsy is a brain disorder that causes people to have recurring seizures. The seizures happen when clusters of nerve cells, or neurons, in the brain send out the wrong signals. People may have strange sensations and emotions or behave strangely. They may have violent muscle spasms or lose consciousness.

Epilepsy has many possible causes, including illness, brain injury, and abnormal brain development. In many cases, the cause is unknown.

Doctors use brain scans and other tests to diagnose epilepsy. It is important to start treatment right away. There is no cure for epilepsy, but medicines can control seizures for most people. When medicines are not working well, surgery or implanted devices such as vagus nerve stimulators may help. Special diets can help some children with epilepsy.

NIH: National Institute of Neurological Disorders and Stroke

Genetic Testing

What is genetic testing?

Genetic testing is a type of medical test that looks for changes in your DNA. DNA is short for deoxyribonucleic acid. It contains the genetic instructions in all living things. Genetic tests analyze your cells or tissue to look for any changes in:

Why is genetic testing done?

Genetic testing may be done for many different reasons, including to:

How is genetic testing done?

Genetic tests are often done on a blood or cheek swab sample. But they may also be done on samples of hair, saliva, skin, amniotic fluid (the fluid that surrounds a fetus during pregnancy), or other tissue. The sample is sent to a laboratory. There, a lab technician will use one of several different techniques to look for genetic changes.

What are the benefits of genetic testing?

The benefits of genetic testing include:

What are the drawbacks of genetic testing?

The physical risks of the different types of genetic testing are small. But there can be emotional, social, or financial drawbacks:

How do I decide whether to be tested?

The decision about whether to have genetic testing is complex. In addition to discussing the test with your health care provider, you can meet with a genetic counselor. Genetic counselors have specialized degrees and experience in genetics and counseling. They can help you understand the tests and weigh the risks and benefits. If you do get a test, they can explain the results and make sure that you have the support that you need.

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