Moxifloxacin is in a class of drugs called fluoroquinolone antibiotics. It works by stopping the life cycle of bacteria. It is used to eliminate certain bacteria that cause infections in your lungs and sinuses. Antibiotics will not work for colds, flu, or other viral infections.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Mifepristone is used alone or in combination with misoprostol (Cytotec) to end an early pregnancy. Early pregnancy means it has been 49 days or less since your last menstrual period began. Mifepristone is in a class of medications called antiprogestational steroids. It works by blocking the activity of progesterone, a substance your body makes to help continue pregnancy.

Magnesium hydroxide is used on a short-term basis to treat constipation.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Masoprocol is used to treat sun-induced skin growths.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Methylergonovine belongs to a class of drugs called ergot alkaloids. Methylergonovine is used to prevent or treat bleeding from the uterus that can happen after childbirth or an abortion.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Miglitol is used, alone or with other drugs, to treat type II (noninsulin-dependent) diabetes (formerly 'adult-onset'), particularly in people whose diabetes cannot be controlled by diet alone. It slows the breakdown and absorption of table sugar and other complex sugars in the small intestine. This process results in decreased blood sugar (hypoglycemia) levels following meals.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Mycophenolate is used with other medications to prevent the body from rejecting kidney, heart, and liver transplants. Mycophenolate is in a class of medications called immunosuppressive agents. It works by weakening the body's immune system so it will not attack and reject the transplanted organ.

Miconazole, an antifungal agent, is used for skin infections such as athlete's foot and jock itch and for vaginal yeast infections.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Mometasone nasal inhalation is used for the treatment and prevention of nasal symptoms of seasonal and year-round allergies, including runny nose, sneezing, and itchy nose. Mometasone nasal inhalation is in a class of medications called topical steroids. It works by reducing inflammation (swelling) in the nasal passages.

Memantine is used to treat the symptoms of Alzheimer's disease. Memantine is in a class of medications called NMDA receptor antagonists. It works by decreasing abnormal excitement in the brain. Memantine can help people with Alzheimer's disease to think more clearly and perform daily activities more easily, but it is not a cure and does not stop the progression of the disease.

Medroxyprogesterone injection is used to prevent pregnancy. Medroxyprogesterone is in a class of medications called progestins. It works by preventing ovulation (the release of eggs from the ovaries). It also changes the lining of the uterus to prevent pregnancy from developing. Medroxyprogesterone injection is a very effective method of birth control but does not prevent the spread of human immunodeficiency virus [HIV, the virus that causes acquired immunodeficiency syndrome (AIDS)] or other sexually transmitted diseases.

Methsuximide is used to treat a type of seizure called absence (petit mal) that cannot be treated with other medications. Methsuximide acts on the brain and nervous system in the treatment of epilepsy.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Metaproterenol is used to prevent and treat wheezing, shortness of breath, and troubled breathing caused by asthma, chronic bronchitis, emphysema, and other lung diseases. It relaxes and opens air passages in the lungs, making it easier to breathe.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Meperidine is used to relieve moderate to severe pain. Meperidine is in a class of medications called narcotic analgesics, a group of pain medications similar to morphine. It works by changing the way the body senses pain.

Methadone is used to relieve severe pain. It also is used in treatment programs for people addicted to narcotics.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Methylphenidate is used to treat attention deficit hyperactivity disorder (ADHD). Methylphenidate (Ritalin, Ritalin-SR) is also used to treat narcolepsy (uncontrolled desire for, or attacks of, sleep). Methylphenidate is in a class of medications called central nervous system (CNS) stimulants. It works by changing the amounts of certain natural substances in the brain.

Methyldopa is used to treat high blood pressure. It works by relaxing the blood vessels so that blood can flow more easily through the body.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Meclofenamate is used to relieve the pain, tenderness, inflammation (swelling), and stiffness caused by arthritis. It is also used to relieve other types of pain, including muscle and menstrual pain and pain after surgery, dental work, or childbirth. It also may be used for heavy menstrual blood loss.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Mesoridazine is used to treat the symptoms of schizophrenia and reduce restlessness, anxiety, and tension. It can also reduce hyperactivity and uncooperativeness.

Metolazone, a 'water pill,' is used to treat high blood pressure and fluid retention caused by various conditions, including heart disease. It causes the kidneys to get rid of unneeded water and salt from the body into the urine.

This medicine is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Methimazole is used to treat hyperthyroidism, a condition that occurs when the thyroid gland produces too much thyroid hormone. It is also taken before thyroid surgery or radioactive iodine therapy.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Meclizine is used to prevent and treat nausea, vomiting, and dizziness caused by motion sickness. It is most effective if taken before symptoms appear.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Methocarbamol, a muscle relaxant, is used with rest, physical therapy, and other measures to relax muscles and relieve pain and discomfort caused by strains, sprains, and other muscle injuries.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Methylprednisolone, a corticosteroid, is similar to a natural hormone produced by your adrenal glands. It is often used to replace this chemical when your body does not make enough of it. It relieves inflammation (swelling, heat, redness, and pain) and is used to treat certain forms of arthritis; skin, blood, kidney, eye, thyroid, and intestinal disorders (e.g., colitis); severe allergies; and asthma. Methylprednisolone is also used to treat certain types of cancer.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Vitamins are natural substances that your body needs to grow, develop, and function normally. Vitamins are contained in food; a well-balanced diet usually provides all of the vitamins required. However, there are times, such as during pregnancy and childhood, when your body needs more vitamins than usual. During certain illnesses, your body either cannot get or cannot efficiently use all of the vitamins it needs.

Multivitamins are prescribed for patients who need extra vitamins, who cannot eat enough food to obtain the required vitamins, or who cannot receive the full benefit of the vitamins contained in the food they eat.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Mometasone is used to relieve the itching and inflammation of numerous skin conditions.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Mesalamine, an anti-inflammatory medicine, is used to treat ulcerative colitis, a condition in which the bowel is inflamed. Mesalamine reduces bowel inflammation, diarrhea (stool frequency), rectal bleeding, and stomach pain.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Misoprostol is used to prevent ulcers in people who take certain arthritis or pain medicines, including aspirin, that can cause ulcers. It protects the stomach lining and decreases stomach acid secretion.

Moexipril is used to treat high blood pressure. It decreases certain chemicals that tighten

the blood vessels, so blood flows more smoothly.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Metformin is used alone or with other medications, including insulin, to treat type 2 (noninsulin-dependent) diabetes. Metformin helps to control the amount of glucose (sugar) in your blood. It decreases the amount of glucose you absorb from your food and the amount of glucose made by your liver. Metformin also increases your body's response to insulin, a natural substance that controls the amount of glucose in the blood. Metformin is not used to treat type 1 (insulin-dependent) diabetes.

Mirtazapine, an antidepressant or mood elevator, is used to treat depression. Mirtazapine is in a class of medications called antidepressants It works by increasing certain types of activity in the brain.

Malathion ( mal-a-THYE-on) belongs to the group of medicines known as pediculicides (medicines that kill lice).

Malathion is applied to the hair and scalp to treat head lice infections. It acts by killing both the lice and their eggs.

This medicine is available only with your doctor's prescription, in the following dosage form:

Topical
• Lotion (U.S.)

Measles (MEE-zills) Virus Vaccine Live is an immunizing agent used to prevent infection by the measles virus. It works by causing your body to produce its own protection (antibodies) against the virus. This vaccine does not protect you against German measles (Rubella). A separate immunization is needed for that type of measles.

Measles (also known as coughing measles, hard measles, morbilli, red measles, rubeola, and ten-day measles) is an infection that is easily spread from one person to another. Infection with measles can lead to serious problems, such as pneumonia, ear infections, sinus problems, convulsions (seizures), brain damage, and possibly death. The risk of serious complications and death is greater for adults and infants than for children and teenagers.

Immunization against measles is recommended for everyone 12 to 15 months of age and older. In addition, there may be special reasons why children from 6 months of age up to 12 months of age may also require measles vaccine.

Immunization against measles is usually not recommended for infants up to 12 months of age, unless the risk of their getting a measles infection is high. This is because antibodies they received from their mothers before birth may interfere with the effectiveness of the vaccine. Children who were immunized against measles before 12 months of age should be immunized twice again.

You can be considered to be immune to measles only if you received two doses of measles vaccine starting on or after your first birthday and have the medical record to prove it, if you have a doctor's diagnosis of a previous measles infection, or if you have had a blood test showing immunity to measles.

This vaccine is to be administered only by or under the supervision of your doctor or other health care professional. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Mecamylamine (mek-a-MILL-a-meen) belongs to the general class of medicines called antihypertensives. It is used to treat high blood pressure (hypertension).

High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.

Mecamylamine works by controlling impulses along certain nerve pathways. As a result, it relaxes blood vessels so that blood passes through them more easily. This helps to lower blood pressure.

Mecamylamine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S.)

Mechlorethamine (me-klor-ETH-a-meen) belongs to the group of medicines called alkylating agents. It is used to treat certain skin conditions that could turn to cancer if left untreated.

Mechlorethamine interferes with the growth of problem cells, which are eventually destroyed. However, there is also a chance that mechlorethamine can cause some kinds of skin cancer, especially after it has been used for several years.

Before you begin treatment with mechlorethamine, you and your doctor should talk about the good this medicine will do as well as the risks of using it.

Mechlorethamine is available only with your doctor's prescription, in the following dosage forms:

Topical
• Ointment (U.S. and Canada)
• Topical solution (U.S. and Canada)

Mefloquine ( ME-floe-kwin) belongs to a group of medicines called antimalarials. It is used to prevent or treat malaria, a red blood cell infection transmitted by the bite of a mosquito.

Malaria transmission occurs in large areas of Central and South America, Hispaniola, sub-Saharan Africa, the Indian subcontinent, Southeast Asia, the Middle East, and Oceania. Country-specific information on malaria can be obtained from the Centers for Disease Control and Prevention (CDC), or from the CDC's web site at http://www.cdc.gov/travel.

This medicine may cause some serious side effects. Therefore, it is usually used only to prevent the symptoms of malaria or to treat serious malaria infections in areas where it is known that other medicines may not work.

Mefloquine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S. and Canada)

Meningococcal polysaccharide (ma-nin-ja-KOK-kal pol-i-SAK-ka-ryd ) vaccine is an active immunizing agent used to prevent infection by certain groups of meningococcal bacteria. The vaccine works by causing your body to produce its own protection (antibodies) against the disease.

The following information applies only to the meningococcal vaccine used for meningococcal bacteria Groups A, C, Y, and W-135. These groups cause approximately 50% of meningococcal meningitis cases in the U.S. The vaccine will not protect against infection caused by other meningococcal bacteria groups, such as Group B.

Meningococcal infection can cause life-threatening illnesses, such as meningococcal meningitis, which affects the brain, and meningococcemia, which affects the blood. Some persons with meningococcal meningitis and/or meningococcemia also may die. These diseases are more likely to occur in young children and in persons with certain diseases or conditions that make them more susceptible to a meningococcal infection or more likely to develop serious problems from a meningococcal infection.

Immunization against meningococcal disease is recommended for persons 2 years of age or older who are at risk of getting the disease because:

• they have certain diseases or conditions that make them more susceptible to a meningococcal infection or more likely to develop serious problems from a meningococcal infection.
• they are living in, working in, or visiting an area where there is a strong possibility of contracting meningococcal disease.

Usually a person needs to receive meningococcal vaccine only once. However, additional injections may be needed for young children who remain at high risk for meningococcal disease.

Meningococcal polysaccharide vaccine is to be administered only by or under the supervision of your doctor or other health care professional. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Meprobamate (me-proe-BA-mate) is used to relieve nervousness or tension. This medicine should not be used for nervousness or tension caused by the stress of everyday life.

Meprobamate is available only with your doctor's prescription, in the following dosage forms:

Oral
• Extended-release capsules (U.S. and Canada)
• Tablets (U.S. and Canada)

Mercaptopurine (mer-kap-toe-PYOOR-een ) belongs to the group of medicines known as antimetabolites. It is used to treat some kinds of cancer.

Mercaptopurine interferes with the growth of cancer cells, which are eventually destroyed. Since the growth of normal body cells may also be affected by mercaptopurine, other effects will also occur. Some of these may be serious and must be reported to your doctor. Other effects may not be serious but may cause concern. Some effects may not occur for months or years after the medicine is used.

Before you begin treatment with mercaptopurine, you and your doctor should talk about the good this medicine will do as well as the risks of using it.

Mercaptopurine may also be used for other conditions as determined by your doctor.

Mercaptopurine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S. and Canada)

Mesna ( MES-na) is used to reduce the harmful effects of some cancer medicines on the bladder.

Mesna is to be given only by or under the immediate supervision of your doctor. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Methotrexate ( meth-o-TREX-ate) belongs to the group of medicines known as antimetabolites. It is used to treat cancer of the breast, head and neck, lung, blood, bone, and lymph, and tumors in the uterus. It may also be used to treat other kinds of cancer, as determined by your doctor.

Methotrexate blocks an enzyme needed by the cell to live. This interferes with the growth of cancer cells, which are eventually destroyed. Since the growth of normal body cells may also be affected by methotrexate, other effects will also occur. Some of these may be serious and must be reported to your doctor. Other effects, like hair loss, may not be serious but may cause concern. Some effects may not occur for months or years after the medicine is used.

Before you begin treatment with methotrexate, you and your doctor should talk about the good this medicine will do as well as the risks of using it.

Methotrexate is available only with your doctor's prescription, in the following dosage forms:

Oral
• Tablets (U.S. and Canada)

Parenteral
• Injection (U.S. and Canada)

Methoxsalen (meth-OX-a-len) belongs to the group of medicines called psoralens. It is used along with ultraviolet light (found in sunlight and some special lamps) in a treatment called PUVA to treat vitiligo, a disease in which skin color is lost, and psoriasis, a skin condition associated with red and scaly patches.

Methoxsalen is also used with ultraviolet light in the treatment of white blood cells. This treatment is called photopheresis and is used to treat the skin problems associated with mycosis fungoides, which is a type of lymphoma.

Methoxsalen may also be used for other conditions as determined by your doctor.

This medicine is available only with your doctor's prescription, in the following dosage forms:

Oral
• Hard gelatin capsules (U.S. and Canada)
• Soft gelatin capsules (U.S. and Canada)

Methyldopa (meth-ill-DOE-pa) belongs to the general class of medicines called antihypertensives. It is used to treat high blood pressure (hypertension).

High blood pressure adds to the work load of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.

Methyldopa works by controlling impulses along certain nerve pathways. As a result, it relaxes blood vessels so that blood passes through them more easily. This helps to lower blood pressure.

Methyldopa is available only with your doctor's prescription, in the following dosage forms:

Oral
• Oral suspension (U.S.)
• Tablets (U.S. and Canada)

Parenteral
• Injection (U.S. and Canada)

Methylphenidate (meth-il-FEN-i-date) belongs to the group of medicines called central nervous system (CNS) stimulants. It is used to treat attention-deficit hyperactivity disorder (ADHD), narcolepsy (uncontrollable desire for sleep or sudden attacks of deep sleep), and other conditions as determined by the doctor.

Methylphenidate works in the treatment of ADHD by increasing attention and decreasing restlessness in children and adults who are overactive, cannot concentrate for very long or are easily distracted, and are impulsive. This medicine is used as part of a total treatment program that also includes social, educational, and psychological treatment.

This medicine is available only with a doctor's prescription. Prescriptions cannot be refilled. A new written prescription must be obtained from your doctor each time you or your child needs this medicine.

Methylphenidate is available in the following dosage forms:

Oral
• Tablets (U.S. and Canada)
• Extended-release tablets (U.S. and Canada)
• Extended-release capsules (U.S.)

Methysergide (meth-i-SER-jide) belongs to the group of medicines known as ergot alkaloids. It is used to prevent migraine headaches and some kinds of throbbing headaches. It is not used to treat an attack once it has started. The exact way methysergide acts on the body is not known.

This medicine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S. and Canada)

Metronidazole (me-troe-NI-da-zole) is used to treat infections. It may also be used for other problems as determined by your doctor. It will not work for colds, flu, or other virus infections.

Metronidazole is available only with your doctor's prescription, in the following dosage forms:

Oral
• Capsules (U.S. and Canada)
• Tablets (U.S. and Canada)

Parenteral
• Injection (U.S. and Canada)

Metyrapone ( me-TEER-a-pone) is used in the diagnosis of certain problems of the adrenal glands. These glands are located near the kidneys. The adrenal glands produce a steroid chemical called cortisol (hydrocortisone) that helps the body respond to stress or illness. From the results of a metyrapone test, your doctor will be able to tell if your adrenal glands produce the correct amount of cortisol under stress or during illnesses.

How test is done: Metyrapone is taken by mouth in one or more doses the day before the testing is done. The next day, blood and/or urine samples are taken. A tube called a catheter may be placed in your bladder to help take the urine sample. The amount of hormones in your blood or urine is measured. Then the results of the test are studied.

Metyrapone may also be used for other conditions as determined by your doctor.

Metyrapone is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S. and Canada)

Mexiletine ( MEX-i-le-teen) belongs to the group of medicines known as antiarrhythmics. It is used to correct irregular heartbeats to a normal rhythm.

Mexiletine produces its helpful effects by slowing nerve impulses in the heart and making the heart tissue less sensitive.

Mexiletine is available only with your doctor's prescription, in the following dosage form:

Oral
• Capsules (U.S. and Canada)

Midazolam ( MID-ay-zoe-lam) is used to produce sleepiness or drowsiness and to relieve anxiety before surgery or certain procedures. It is also used to produce loss of consciousness before and during surgery. Midazolam is used sometimes in patients in intensive care units in hospitals to cause unconsciousness. This may allow the patients to withstand the stress of being in the intensive care unit and help the patients cooperate when a machine must be used to assist them with breathing.

Midazolam is given only by or under the immediate supervision of a doctor trained to use this medicine. If you will be receiving midazolam during surgery, your doctor or anesthesiologist will give you the medicine and closely follow your progress.

Midazolam is available in the following dosage forms:

Oral
• Oral solution (U.S.)

Parenteral
• Injection (U.S. and Canada)

Minoxidil (mi-NOX-i-dil) applied to the scalp is used to stimulate hair growth in adult men and women with a certain type of baldness. The exact way that this medicine works is not known.

If hair growth is going to occur with the use of minoxidil, it usually occurs after the medicine has been used for several months and lasts only as long as the medicine continues to be used. Hair loss will begin again within a few months after minoxidil treatment is stopped.

In the U.S., this medicine is available without a prescription. In Canada, this medicine is available only with your doctor's prescription. It is available in the following dosage form:

Topical
• Topical solution (U.S. and Canada)

Mitomycin ( mye-toe-MYE-sin) belongs to the group of medicines known as antineoplastics. It is used to treat some kinds of cancer.

Mitomycin interferes with the growth of cancer cells, which are eventually destroyed. Since the growth of normal body cells may also be affected by mitomycin, other effects will also occur. Some of these may be serious and must be reported to your doctor. Other effects, like hair loss, may not be serious but may cause concern. Some effects may not occur for months or years after the medicine is used.

Before you begin treatment with mitomycin, you and your doctor should talk about the good this medicine will do as well as the risks of using it.

Mitomycin is to be administered only by or under the immediate supervision of your doctor. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Mitoxantrone ( mye-toe-ZAN-trone) belongs to the general group of medicines known as antineoplastics. It is used to treat some kinds of cancer. It is also used to treat some forms of multiple sclerosis (MS). This medicine will not cure MS, but may extend the time between relapses.

Mitoxantrone seems to interfere with the growth of cancer cells, which are eventually destroyed. Since the growth of normal body cells may also be affected by mitoxantrone, other effects will also occur. Some of these may be serious and must be reported to your doctor. Other effects, like hair loss, may not be serious but may cause concern. Some effects may not occur for months or years after the medicine is used.

Before you begin treatment with mitoxantrone, you and your doctor should talk about the good this medicine will do as well as the risks of using it.

Mitoxantrone is to be administered only by or under the immediate supervision of your doctor. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Monoctanoin (mon-OCK-ta-noyn ) is used to dissolve cholesterol gallstones. Gallstones, which are found in the gallbladder or bile duct, sometimes remain in the bile duct even after the gallbladder has been removed by surgery. These stones may be too large to pass out of the body on their own. A catheter or tube is used to put the solution of monoctanoin into the bile duct where it will come in contact with the gallstone or gallstones and dissolve them. This process continues for 2 to 10 days.

Monoctanoin is administered only by or under the supervision of your doctor. It is available in the following dosage form:

Local
• Irrigation (U.S.)

Mumps Virus Vaccine Live is an active immunizing agent used to prevent infection by the mumps virus. It works by causing your body to produce its own protection (antibodies) against the virus infection.

Mumps is an infection that can cause serious problems, such as encephalitis and meningitis, which affect the brain. In addition, adolescent boys and men are very susceptible to a condition called orchitis, which causes pain and swelling in the testicles and scrotum and, in rare cases, sterility. Also, mumps infection can cause spontaneous abortion in women during the first 3 months of pregnancy.

Immunization against mumps is recommended for all persons 12 months of age or older.

Immunization against mumps is not recommended for infants less than 12 months of age, because antibodies they received from their mothers before birth may interfere with the effectiveness of the vaccine. Children who were immunized against mumps before 12 months of age should be immunized again.

You can be considered to be immune to mumps only if you:

• received mumps vaccine on or after your first birthday and have the medical record to prove it, or
• have a doctor's diagnosis of a previous mumps infection, or
• have had a laboratory test that shows that you are immune to mumps.

This vaccine is to be administered only by or under the supervision of your doctor or other health care professional. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Muromonab-CD3 (myoo-roe-MOE-nab cee-dee-three) is a monoclonal antibody. It is used to reduce the body's natural immunity in patients who receive organ (for example, kidney) transplants.

When a patient receives an organ transplant, the body's white blood cells will try to get rid of (reject) the transplanted organ. Muromonab-CD3 works by preventing the white blood cells from doing this.

The effect of muromonab-CD3 on the white blood cells may also reduce the body's ability to fight infections. Before you begin treatment, you and your doctor should talk about the good this medicine will do as well as the risks of using it.

Muromonab-CD3 is to be administered only by or under the immediate supervision of your doctor. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Measles, mumps, and rubella (MEE-zills and rue-BELL-a) virus vaccine live is an active immunizing agent used to prevent infection by the measles, mumps, and rubella viruses. It works by causing your body to produce its own protection (antibodies) against the virus.

Measles (also known as coughing measles, hard measles, morbilli, red measles, rubeola, and 10-day measles) is an infection that is easily spread from one person to another. Infection with measles can cause serious problems, such as stomach problems, pneumonia, ear infections, sinus problems, convulsions (seizures), brain damage, and possibly death. The risk of serious complications and death is greater for adults and infants than for children and teenagers.

Mumps is an infection that can cause serious problems, such as encephalitis and meningitis, which affect the brain. In addition, adolescent boys and men are very susceptible to a condition called orchitis, which causes pain and swelling in the testicles and scrotum and, in rare cases, sterility. Also, mumps infection can cause spontaneous abortion (miscarriage) in women during the first 3 months of pregnancy.

Rubella (also known as German measles) is a serious infection that causes miscarriages, stillbirths, or birth defects in unborn babies when pregnant women get the disease.

While immunization against measles, mumps, and rubella is recommended for all persons 12 months of age and older, it is especially important for women of childbearing age and persons traveling outside the U.S.

If measles, mumps, and rubella vaccine is to be given to a child, the child should be at least 12 months of age. This is to make sure the measles vaccine is effective. In a younger child, antibodies from the mother may interfere with the effectiveness of the vaccine.

This vaccine should be administered only by or under the supervision of your doctor or other health care professional. It is available in the following dosage form:

Parenteral
• Injection (U.S. and Canada)

Mibefradil (mi-be-FRA-dil) belongs to a group of medicines called calcium channel blocking agents, or, more commonly, calcium channel blockers.

Calcium channel blocking agents affect the movement of calcium into the cells of the heart and blood vessels. As a result, they relax blood vessels and increase the supply of blood and oxygen to the heart while reducing its workload.

Mibefradil is used to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.

Mibefradil is also used to treat recurring chest pain (angina pectoris). Angina occurs when the vessels that carry blood to the heart become narrowed and blocked, reducing the supply of blood and oxygen to the heart. As a result, chest tightness and/or a pressing or squeezing pain can occur. Mibefradil is thought to reduce angina by increasing the supply of blood and oxygen to the heart.

Mibefradil may also be used for other conditions as determined by your doctor.

The medicine was withdrawn from the U.S. market in May 1998.

Mangafodipir (man-ga-FOE-di-peer) is an MRI (magnetic resonance imaging) contrast agent (also known as paramagnetic agents). MRI agents are used to help provide a clear picture during MRI. MRI is a special kind of diagnostic procedure. It uses magnets and computers to create images or "pictures" of certain areas inside the body. Unlike x-rays, it does not involve ionizing radiation.

Mangafodipir is given by injection before MRI to help diagnose problems in the liver.

Mangafodipir is injected into a vein. The dose of this agent will be different for different patients depending on the body weight of the person.

This medicine is to be used only by or under the supervision of a doctor. It is available in the following dosage form:

Parenteral
• Injection (U.S.)

Mupirocin ( myoo-PEER-oh-sin) is used inside the nose to kill a certain bacteria, known as Staphylococcus aureus (also known as "staph"), that has become resistant to the antibiotic methicillin.

This medicine is available only with your doctor's prescription, in the following dosage form:

Nasal
• Nasal ointment (U.S.)

Meropenem ( mer-oh-PEN-em) is used in the treatment of infections caused by bacteria. It works by killing bacteria or preventing their growth. This medicine will not work for colds, flu, or other virus infections.

This medicine is available only with your doctor's prescription, in the following dosage form:

Parenteral
• Injection (U.S.)

Montelukast (mon-te-LOO-kast) is used in mild to moderate asthma to decrease the symptoms of asthma and the number of acute asthma attacks. However, this medicine should not be used to relieve an asthma attack that has already started. This medicine is also used to treat the symptoms (sneezing, runny nose, itching, wheezing) of seasonal (short-term) allergies.

This medicine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S.)
• Chewable tablets (U.S.)
• Oral granules (U.S.)

Methoxsalen (meth-OX-a-len) belongs to the group of medicines called psoralens. It is used along with ultraviolet light (found in sunlight and some special lamps) to treat the white blood cells from your blood in a process called photopheresis. The treated white blood cells are returned to your body to control skin problems associated with cutaneous T-cell lymphoma, a cancer of the lymph system.

Methoxsalen is to be administered only by or under the supervision of your doctor or other health care professional. It is available in the following dosage form:

Extracorporeal
• Sterile solution (U.S.)

Moclobemide ( moe-KLOE-be-mide)

is a monoamine oxidase (MAO) inhibitor used to relieve certain types of mental depression. It works by blocking the action of a chemical substance known as monoamine oxidase (MAO) in the nervous system.

Although this medicine is very effective for certain patients, it may also cause some unwanted reactions if not taken in the right way. It is very important to avoid certain beverages and medicines while you are being treated with an MAO inhibitor. Your doctor may provide a list as a reminder of which products you should avoid.

This medicine is available only with your doctor's prescription, in the following dosage forms:

Oral
• Moclobemide
  • Tablets (Canada)

Mifepristone ( mif-i-PRIS-tone) is used to end a pregnancy that is less than 49 days in duration. It works by stopping the supply of hormones that maintains the interior of the uterus. Without these hormones, the uterus cannot support the pregnancy and the contents of the uterus are expelled.

This medicine is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S.)

Contraceptives are designed to prevent pregnancy. The combination of medroxyprogesterone ( me-DROX-ee-proe-JES-ter-rone) and estradiol ( es-tra-DYE-ole) are two types of hormones that work by stopping a women's egg from fully developing each month. The egg can no longer accept sperm and fertilization is prevented. Although contraceptives have other effects that help prevent a pregnancy from occurring, this is the main action

This medicine is available only with your doctor's prescription, in the following dosage forms:

Parenteral
• Injection (U.S.)

Memantine (me-MAN-teen) is used to treat moderate to severe Alzheimer's disease. Memantine is not a cure for Alzheimer's disease but it can help people with the disease. Memantine will not cure Alzheimer's disease, and it will not stop the disease from getting worse.

This medicine is available only with your doctor's prescription, in the following dosage forms:

Oral
• Solution (U.S.)
• Tablets (U.S.)

Moxifloxacin (mox-ee-FLOX-a-sin) belongs to the family of medicines called antibiotics. Moxifloxacin ophthalmic solution (eye drops) is used to treat infections of the eye, such as bacterial conjunctivitis. Ophthalmic moxifloxacin works by killing the bacteria in your eye.

This medicine is available only with your doctor's prescription, in the following dosage forms:

Ophthalmic
• Ophthalmic solution (eye drops) (U.S.)