pharmacogenetic

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.

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:

• Two drugs, such as aspirin and blood thinners
• Drugs and food, such as statins and grapefruit
• Drugs and supplements, such as gingko and blood thinners
• Drugs and medical conditions, such as aspirin and peptic ulcers

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

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.

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.

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 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 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.

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

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:

• Selective serotonin reuptake inhibitors (SSRIs)
• Serotonin and norepinephrine reuptake inhibitors (SNRIs)
• Atypical antidepressants, which are newer antidepressants that don't fit into the other 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.

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:

• Which symptoms bother you most? Some antidepressants may do a better job helping specific symptoms, such as trouble sleeping.
• What other medicines and supplements do you take? Some antidepressants can cause problems if you take them with certain medicines and herbs.
• Did a certain antidepressant work well for a close relative? An antidepressant that helped a parent, brother, or sister could be a good choice for you, too.
• Do you have other health conditions? Certain antidepressants can make some other conditions better or worse. Any other conditions that you have will be part of choosing your depression treatment.
• Are you pregnant, planning for pregnancy, or breastfeeding? If so, your provider will help you find a way to treat your depression that's safe for you and your baby.

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.

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.

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:

• Nausea and vomiting
• Weight gain
• Diarrhea
• Sleepiness
• Sexual problems, such as a lack of desire or ability to have sex

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.

Antidepressants are generally safe when you use them correctly:

• Tell your provider about everything you take. That includes medicines, herbs, supplements, and over-the-counter medicines you take, such as pain relievers and decongestants. Be honest about recreational drugs and alcohol, too.
• Try to get all your medicines from the same pharmacy. That way the pharmacist can warn you and your provider if you take medicines that may cause problems when used together.
• Follow all instructions about how to take your medicine.
• Talk with your provider if side effects bother you.
• Never stop taking antidepressants without your provider's help. Stopping too fast may make depression come back. You could even make your condition worse. To stop antidepressants safely, you need to give your body time to get used to being without the medicine. Your provider can tell you the safest way to go off an antidepressant.

NIH: National Institute of Mental Health

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:

• Having trouble paying attention (inattention)
• Having trouble controlling impulsive behaviors (impulsivity)
• Being overly active (hyperactivity)

There are three types of ADHD:

• Mostly Inattentive ADHD. People with this type of ADHD have trouble paying attention and are easily distracted. It's hard for them to organize or finish tasks. They may have trouble following instructions or conversations.
• Mostly Hyperactive-Impulsive ADHD. People with this type of ADHD have symptoms of both hyperactivity and impulsivity:
  • With hyperactivity, people feel a need to always be moving. They have trouble sitting still and may fidget and/or talk too much.
  • With impulsivity, people have trouble controlling their actions and words. They tend to act on sudden ideas or feelings without thinking about the possible results. They may interrupt others a lot or have trouble waiting their turn.
• Combined ADHD. People with this type of ADHD have a mix of inattentive and hyperactive-impulsive symptoms. Combined ADHD is the most common type.

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.

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.

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

People with symptoms of attention problems may often:

• Miss details or make careless mistakes in schoolwork, at work, or in other activities
• Have trouble staying focused on play activities or work tasks
• Not seem to listen when spoken to directly
• Find it hard to follow instructions or finish tasks, or may start but get easily sidetracked
• Have trouble being organized, keeping belongings in order, and managing time
• Avoid doing tasks that require long periods of mental effort
• Lose important items, such as books, wallets, keys, eyeglasses, and cellphones
• Forget about doing daily activities

People with symptoms of hyperactivity-impulsivity may often:

• Fidget and squirm while seated
• Get up when staying seated is expected, such as at school or work
• Run around or climb when it's not appropriate (children) or feel restless (teens and adults)
• Have trouble doing quiet activities
• Be constantly moving or "on the go"
• Talk much more than is normal
• Blurt out answers before questions are completed
• Have trouble waiting for their turn
• Interrupt others for example during conversations or games

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

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:

• Several symptoms of ADHD that began before age 12.
• Several symptoms of inattention and/or hyperactivity-impulsivity that have lasted for at least 6 months and cause serious problems:
• For children up to age 16, there must be at least 6 ongoing symptoms.
• For people 17 and older, there must be at least 5 ongoing symptoms.
• Symptoms that happen in 2 or more settings, for example, at home and at work or school.
• Symptoms that clearly get in the way of functioning well at school, work, and/or in social situations.
• Symptoms aren't caused by another mental health disorder.

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

• Medicines.
• Psychotherapy (talk therapy), including behavior therapy.
• Education or training for parents to give them the skills and strategies to help their child. This is especially important for younger children.
• A combination of these treatments.

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

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.

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.

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.

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.

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,:

• Learn about the health conditions in your family history. What health problems did your grandparents, aunts, uncles, and cousins have? Write down what you learn and share it with your doctor.
• Keep track of your symptoms, including how long they last and what makes them better or worse. Share your notes with your doctor.
• See a specialist who deals with the symptoms that bother you most. For example, if you have rash, see a dermatologist (skin doctor).

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 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.

You may need a blood thinner if you have:

• Certain heart or blood vessel diseases
• An abnormal heart rhythm called atrial fibrillation
• A heart valve replacement
• A risk of blood clots after surgery
• Congenital heart defects

There are different types of blood thinners:

• Anticoagulants, such as heparin or warfarin (also called Coumadin), slow down your body's process of making clots.
• Antiplatelets, such as aspirin and clopidogrel, prevent blood cells called platelets from clumping together to form a clot. Antiplatelets are mainly taken by people who have had a heart attack or stroke.

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.

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:

• Menstrual bleeding that is much heavier than normal
• Red or brown urine
• Bowel movements that are red or black
• Bleeding from the gums or nose that does not stop quickly
• Vomit that is brown or bright red
• Coughing up something red
• Severe pain, such as a headache or stomachache
• Unusual bruising
• A cut that does not stop bleeding
• A serious fall or bump on the head
• Dizziness or weakness

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:

• White blood cells help your body fight infection
• Red blood cells deliver oxygen from your lungs to your tissues and organs
• Platelets help form clots to stop bleeding

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.

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:

• Acute lymphocytic leukemia (ALL), which is the most common type of leukemia in children and the most common cancer in children. In ALL, the bone marrow makes too many lymphocytes, a type of white blood cell.
• Acute myeloid leukemia (AML), which happens when bone marrow makes abnormal myeloblasts (a type of white blood cell), red blood cells, or platelets.

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

• Chronic lymphocytic leukemia (CLL), in which the bone marrow makes abnormal lymphocytes (a type of white blood cell). It is more common in teens than children.
• Chronic myeloid leukemia (CML), in which the bone marrow makes abnormal granulocytes (a type of white blood cell). It is very rare in children.

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

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.

The factors that raise the risk of childhood leukemia include:

• Having a brother or sister, especially a twin, with leukemia
• Past treatment with chemotherapy
• Exposure to radiation, including radiation therapy
• Having certain genetic conditions, such as
  • Ataxia telangiectasia
  • Down syndrome
  • Fanconi anemia
  • Li-Fraumeni syndrome
  • Neurofibromatosis type 1

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

Some of the symptoms of leukemia may include:

• Feeling tired
• Fever or night sweats
• Easy bruising or bleeding
• Weight loss or loss of appetite
• Petechiae, which are tiny red dots under the skin. They are caused by bleeding.

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

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

• A physical exam
• A medical history
• Blood tests, such as a complete blood count (CBC)
• Bone marrow tests. There are two main types - bone marrow aspiration and bone marrow biopsy. Both tests involve removing a sample of bone marrow and bone. The samples are sent to a lab for testing.
• Genetic tests to look for gene and chromosome changes

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).

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:

• chemotherapy
• radiation therapy
• Chemotherapy with stem cell transplant
• Targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells

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

Your body needs some cholesterol to work properly. But if you have too much 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 travels through the blood on proteins called lipoproteins. One type, 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.

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

Your health care provider may prescribe medicine if:

• You have already had a heart attack or stroke, or you have peripheral arterial disease
• Your LDL (bad) cholesterol level is 190 mg/dL or higher
• You are 40-75 years old, you have diabetes, and your LDL cholesterol level is 70 mg/dL or higher
• You are 40-75 years old, you have a high risk of developing heart disease or stroke, and your LDL cholesterol level is 70 mg/dL or higher

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

• Statins, which block the liver from making cholesterol
• Bile acid sequestrants, which decrease the amount of fat absorbed from food
• Cholesterol absorption inhibitors, which decrease the amount of cholesterol absorbed from food and lower triglycerides.
• Nicotinic acid (niacin), which lowers LDL (bad) cholesterol and triglycerides and raises HDL (good) cholesterol. Even though you can buy niacin without a prescription, you should talk to your health care provider before taking it to lower your cholesterol. High doses of niacin can cause serious side effects.
• PCSK9 inhibitors, which block a protein called PCSK9. This helps your liver remove and clear LDL cholesterol from your blood.
• Fibrates, which lower triglycerides. They may also raise HDL (good) cholesterol. If you take them with statins, they may increase the risk of muscle problems.
• Combination medicines, which include more than one type of cholesterol-lowering medicine

There are also a few other cholesterol medicines (lomitapide and mipomersen) that are only for people who have familial hypercholesterolemia (FH). FH is an inherited disorder that causes high LDL cholesterol.

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

• Your cholesterol levels
• Your risk for heart disease and stroke
• Your age
• Any other health problems you have
• Possible side effects of the medicines. Higher doses are more likely to cause side effects, especially over time.

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 you cholesterol levels are in a healthy range.

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 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:

• Genes, which are parts of DNA that carry the information needed to make a protein
• Chromosomes, which are thread-like structures in your cells. They contain DNA and proteins.
• Proteins, which do most of the work in your cells. Testing can look for changes in the amount and activity level of proteins. If it finds changes, it might be due to changes in your DNA.

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

• Find genetic diseases in unborn babies. This is one type of prenatal testing.
• Screen newborn babies for certain treatable conditions
• Lower the risk of genetic diseases in embryos that were created using assisted reproductive technology
• Find out if you carry a gene for a certain disease that could be passed on to your children. This is called carrier testing.
• See whether you are at increased risk of developing a specific disease. This may be done for a disease that runs in your family.
• Diagnose certain diseases
• Identify genetic changes that may be causing or contributing to a disease that you were already diagnosed with
• Figure out how severe a disease is
• Help guide your doctor in deciding the best medicine and dosage for you. This is called pharmacogenomic testing.

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.

The benefits of genetic testing include:

• Helping doctors make recommendations for treatment or monitoring
• Giving you more information for making decisions about your health and your family's health:
  • If you find out that you are at risk for a certain disease, you might take steps to lower that risk. For example, you may find out that you should be screened for a disease earlier and more often. Or you might decide to make healthy lifestyle changes.
  • If you find out that you are not at risk for a certain disease, then you can skip unnecessary checkups or screenings
  • A test could give you information that helps you make decisions about having children
• Identifying genetic disorders early in life so treatment can be started as soon as possible

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

• Depending on the results, you may feel angry, depressed, anxious, or guilty. This can be especially true if you are diagnosed with a disease that does not have effective treatments.
• You may be worried about genetic discrimination in employment or insurance
• Genetic testing may give you limited information about a genetic disease. For example, it cannot tell you whether you will have symptoms, how severe a disease might be, or whether a disease will get worse over time.
• Some genetic tests are expensive, and health insurance might only cover part of the cost. Or they may not cover it at all.

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.