Nevirapine is used to treat human immunodeficiency virus (HIV) infection in patients with or without acquired immunodeficiency syndrome (AIDS). Nevirapine is always used along with at least one other antiviral medication to reduce the amount of virus in the blood. Nevirapine is not a cure and may not decrease the number of HIV-related illnesses. Nevirapine does not prevent the spread of HIV to other people.

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

Naratriptan is used to treat migraine headaches. However, it will not prevent migraine headaches or reduce the number of attacks you have.

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

Nitroglycerin skin patches are used to prevent chest pain (angina). They work by relaxing the blood vessels to the heart, so the blood flow and oxygen supply to the heart is increased.

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

The combination of nystatin and triamcinolone is used to treat fungal skin infections. It relieves itching, inflammation, and pain.

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

Nedocromil is used to treat itchy eyes caused by allergies. Symptoms of allergies occur when cells in your body called mast cells release substances after you come in contact with something to which you are allergic. Nedocromil is in a class of drugs called mast cell stabilizers. It works by stopping the release of these substances.

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

Nitazoxanide is used to treat certain types of infectious diarrhea in children between the ages of 1 and 11 years. Nitazoxanide is in a class of medications called antiprotozoals. It works by stopping the growth of the infecting organisms.

Norethindrone is used to treat endometriosis, a condition in which the type of tissue that lines the uterus (womb) grows in other areas of the body and causes pain, heavy or irregular menstruation (periods), and other symptoms. Norethindrone is also used to treat abnormal periods or bleeding and to bring on a normal menstrual cycle in women who menstruated normally in the past but have not menstruated for at least 6 months and who are not pregnant or undergoing menopause (change of life). Norethindrone is also used as a test to see if the body is producing certain female hormones (natural substances that affect the uterus). Norethindrone is in a class of medications called progestins. It works by stopping the lining of the uterus from growing and by causing the uterus to produce certain hormones.

Norethindrone is also used to prevent pregnancy. Norethindrone is sold under different brand names and is taken in smaller amounts when it used to prevent pregnancy. This monograph does not include information on the use of norethindrone to prevent pregnancy. If you would like more information on that use of norethindrone, read the monograph called "Progestin Only Oral Contraceptives".

Nalidixic acid, an antibiotic, eliminates bacteria that cause urinary tract infections. 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.

Nitrofurantoin, an antibiotic, eliminates bacteria that cause urinary tract infections. 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.

Niacin is used with diet changes (restriction of cholesterol and fat intake) to reduce the amount of cholesterol and certain fatty substances in your blood. Niacin is also used to prevent and treat pellagra (niacin deficiency), a disease caused by inadequate diet and other medical problems. Niacin is a B-complex vitamin.

Nadolol is used alone or in combination with other medications to treat high blood pressure. It is also used to prevent angina (chest pain). Nadolol is in a class of medications called beta blockers. It works by slowing the heart rate and relaxing the blood vessels so the heart does not have to pump as hard.

Nystatin is used to treat fungal infections of the skin, mouth, vagina, and intestinal tract. Fungal medicines 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.

Nicotine chewing gum is used to help people stop smoking cigarettes. It acts as a substitute oral activity and provides a source of nicotine that reduces the withdrawal symptoms experienced when smoking is stopped.

Naltrexone is used to help people who have a narcotic or alcohol addiction stay drug free. Naltrexone is used after the patient has stopped taking drugs or alcohol. It works by blocking the effects of narcotics or by decreasing the craving for alcohol.

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

Naftifine is used for skin infections such as athlete's foot, jock itch, and ringworm.

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

Nabumetone is used to relieve the pain, tenderness, inflammation (swelling), and stiffness caused by osteoarthritis and rheumatoid arthritis. Nabumetone is in a class of medications called nonsteroidal anti-inflammatory medications (NSAIDs). It works by stopping the body's production of a substance that causes pain, fever, and inflammation.

Nizatidine is used to treat and prevent the recurrence of ulcers and to treat other conditions where the stomach makes too much acid. Nizatidine also is used to treat or prevent occasional heartburn, acid indigestion, or sour stomach. It decreases the amount of acid made in the stomach. Nizatidine is available with and without a prescription.

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

Nicardipine is used to treat high blood pressure. It relaxes your blood vessels so your heart does not have to pump as hard. It also increases the supply of blood and oxygen to the heart to control chest pain (angina). If taken regularly, nicardipine controls chest pain, but it does not stop chest pain once it starts. Your doctor may give you a different medication to take when you have chest pain.

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

Nelfinavir is used in combination with other drugs, such as zidovudine (AZT), to treat human immunodeficiency virus (HIV) infections in patients with or without acquired immunodeficiency syndrome (AIDS). Nelfinavir is one of a class of drugs called protease (pro' tee ace) inhibitors, which slow the spread of HIV infection in the body.

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

Nateglinide is used alone or in combination with other medications to treat type 2 (noninsulin-dependent) diabetes (formerly called 'adult-onset') in people whose diabetes cannot be controlled by diet and exercise alone. Nateglinide belongs to a class of drugs called meglitinides. Nateglinide helps your body regulate the amount of glucose (sugar) in your blood. It decreases the amount of glucose by stimulating the pancreas to release insulin.

Naftifine (NAF-ti-feen) is used to treat fungus infections. It works by killing the fungus or preventing its growth.

Naftifine is applied to the skin to treat:

• athlete's foot (ringworm of the foot; tinea pedis);
• jock itch (ringworm of the groin; tinea cruris); and
• ringworm of the body (tinea corporis).

This medicine may also be used for other fungus infections of the skin as determined by your doctor.

Naftifine is available with or without your doctor's prescription, in the following dosage forms:

Topical
• Cream (U.S. and Canada)
• Gel (U.S. and Canada)

Naltrexone (nal-TREK-zone) is used to help narcotic addicts who have stopped taking narcotics to stay drug-free. It is also used to help alcoholics stay alcohol-free. The medicine is not a cure for addiction. It is used as part of an overall program that may include counseling, attending support group meetings, and other treatment recommended by your doctor.

Naltrexone is not a narcotic. It works by blocking the effects of narcotics, especially the ``high'' feeling that makes you want to use them. It also may block the ``high'' feeling that may make you want to use alcohol. It will not produce any narcotic-like effects or cause mental or physical dependence. It will not prevent you from becoming impaired while drinking alcohol.

Naltrexone will cause withdrawal symptoms in people who are physically dependent on narcotics. Therefore, naltrexone treatment is started after you are no longer dependent on narcotics. The length of time this takes may depend on which narcotic you took, the amount you took, and how long you took it. Before you start taking this medicine, be sure to tell your doctor if you think you are still having withdrawal symptoms.

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

Oral
• Tablets (U.S. and Canada)

Narcotic (nar-KOT-ik) analgesics (an-al-JEE-zicks) are used to relieve pain. Some of these medicines are also used just before or during an operation to help the anesthetic work better. Codeine and hydrocodone are also used to relieve coughing. Methadone is also used to help some people control their dependence on heroin or other narcotics. Narcotic analgesics may also be used for other conditions as determined by your doctor.

Narcotic analgesics act in the central nervous system (CNS) to relieve pain. Some of their side effects are also caused by actions in the CNS.

If a narcotic is used for a long time, it may become habit-forming (causing mental or physical dependence). Physical dependence may lead to withdrawal side effects when you stop taking the medicine.

These medicines are available only with your medical doctor's or dentist's prescription. For some of them, prescriptions cannot be refilled and you must obtain a new prescription from your medical doctor or dentist each time you need the medicine. In addition, other rules and regulations may apply when methadone is used to treat narcotic dependence.

These medicines are available in the following dosage forms:

Oral
• Anileridine
  • Tablets (Canada)
• Codeine
  • Oral solution (U.S. and Canada)
  • Tablets (U.S. and Canada)
• Hydrocodone
  • Syrup (Canada)
  • Tablets (Canada)
• Hydromorphone
  • Extended-release capsule (U.S. and Canada)
  • Oral solution (U.S. and Canada)
  • Tablets (U.S. and Canada)
• Levorphanol
  • Tablets (U.S. and Canada)
• Meperidine
  • Syrup (U.S.)
  • Tablets (U.S. and Canada)
• Methadone
  • Oral concentrate (U.S.)
  • Oral solution (U.S.)
  • Tablets (U.S.)
  • Dispersible tablets (U.S.)
• Morphine
  • Capsules (U.S.)
  • Extended-release capsules (U.S. and Canada)
  • Oral solution (U.S. and Canada)
  • Syrup (Canada)
  • Tablets (U.S. and Canada)
  • Extended-release tablets (U.S. and Canada)
• Oxycodone
  • Oral solution (U.S.)
  • Tablets (U.S. and Canada)
  • Extended-release tablets (U.S. and Canada)
• Pentazocine
  • Tablets (Canada)
• Pentazocine and Naloxone
  • Tablets (U.S.)
• Propoxyphene
  • Capsules (U.S. and Canada)
  • Oral suspension (U.S.)
  • Tablets (U.S. and Canada)

Parenteral
• Buprenorphine
  • Injection (U.S.)
• Butorphanol
  • Injection (U.S.)
• Codeine
  • Injection (U.S. and Canada)
• Hydromorphone
  • Injection (U.S. and Canada)
• Levorphanol
  • Injection (U.S. and Canada)
• Meperidine
  • Injection (U.S. and Canada)
• Methadone
  • Injection (U.S.)
• Morphine
  • Injection (U.S. and Canada)
• Nalbuphine
  • Injection (U.S. and Canada)
• Opium
  • Injection (Canada)
• Oxymorphone
  • Injection (U.S. and Canada)
• Pentazocine
  • Injection (U.S. and Canada)

Rectal
• Hydromorphone
  • Suppositories (U.S. and Canada)
• Morphine
  • Suppositories (U.S. and Canada)
• Oxycodone
  • Suppositories (Canada)
• Oxymorphone
  • Suppositories (U.S. and Canada)

Combination medicines containing narcotic analgesics (nar-KOT-ik an-al-JEE-zicks) and acetaminophen ( a-seat-a-MIN-oh-fen) are used to relieve pain. A narcotic analgesic and acetaminophen used together may provide better pain relief than either medicine used alone. In some cases, relief of pain may come at lower doses of each medicine.

Narcotic analgesics act in the central nervous system (CNS) to relieve pain. Many of their side effects are also caused by actions in the CNS. When narcotics are used for a long time, your body may get used to them so that larger amounts are needed to relieve pain. This is called tolerance to the medicine. Also, when narcotics are used for a long time or in large doses, they may become habit-forming (causing mental or physical dependence). Physical dependence may lead to withdrawal symptoms when you stop taking the medicine.

Acetaminophen does not become habit-forming when taken for a long time or in large doses, but it may cause other unwanted effects, including liver damage, if too much is taken.

In the U.S., these medicines are available only with your medical doctor's or dentist's prescription. In Canada, some acetaminophen, codeine, and caffeine combinations are available without a prescription.

These medicines are available in the following dosage forms:

Oral
• Acetaminophen and Codeine
  • Capsules (U.S.)
  • Oral solution (U.S. and Canada)
  • Oral suspension (U.S.)
  • Tablets (U.S. and Canada)
• Acetaminophen, Codeine, and Caffeine
  • Tablets (Canada)
• Dihydrocodeine, Acetaminophen, and Caffeine
  • Capsules (U.S.)
• Hydrocodone and Acetaminophen
  • Capsules (U.S.)
  • Oral solution (U.S.)
  • Tablets (U.S.)
• Oxycodone and Acetaminophen
  • Capsules (U.S.)
  • Oral solution (U.S.)
  • Tablets (U.S. and Canada)
• Pentazocine and Acetaminophen
  • Tablets (U.S.)
• Propoxyphene and Acetaminophen
  • Tablets (U.S.)

Natamycin (na-ta-MYE-sin) belongs to the group of medicines called antifungals. It is used to treat some types of fungus infections of the eye.

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

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

Oral neomycin (nee-oh-MYE-sin) is used to help lessen the symptoms of hepatic coma, a complication of liver disease. In addition, it may be used with another medicine before any surgery affecting the bowels to help prevent infection during surgery.

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

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

Neomycin and polymyxin B (nee-oh-MYE-sin and pol-i-MIX-in bee) combination is used to prevent bacterial infections. It works by killing bacteria.

Neomycin and polymyxin B cream is applied to the skin to prevent minor bacterial skin infections. It may also be used for other problems as determined by your doctor.

This medicine is available without a prescription; however, your doctor may have special instructions on the proper use of this medicine for your medical problem.

Neomycin and polymyxin B combination is available in the following dosage form:

Topical
• Cream (U.S.)

Neomycin, Polymyxin B, and Bacitracin (nee-oh-MYE-sin, pol-i-MIX-in bee, and bass-i-TRAY-sin ) is a combination antibiotic medicine used to help prevent infections of the skin.

Neomycin, polymyxin B, and bacitracin combination is available without a prescription; however, your doctor may have special instructions on the proper use of this medicine for your medical problem.

Topical neomycin, polymyxin B, and bacitracin combination is available in the following dosage form:

Topical
• Ointment (U.S. and Canada)

Neomycin, polymyxin B, and hydrocortisone (nee-oh-MYE-sin, pol-i-MIX-in bee, and hye-droe-KOR-ti-sone ) is a combination antibiotic and cortisone-like medicine. It is used to treat infections of the eye and to help provide relief from redness, irritation, and discomfort of certain eye problems. It is also used to help prevent permanent damage of certain eye problems.

Neomycin, polymyxin B, and hydrocortisone combination is available only with your doctor's prescription, in the following dosage form:

Ophthalmic
• Ophthalmic suspension (eye drops) (U.S. and Canada)

Niacin (NYE-a-sin) is used to help lower high cholesterol and fat levels in the blood. This may help prevent medical problems caused by cholesterol and fat clogging the blood vessels.

Some strengths of niacin are available only with your doctor's prescription. Others are available without a prescription, since niacin is also a vitamin. However, it is best to take it only under your doctor's direction so that you can be sure you are taking the correct dose.

Niacin for use in the treatment of high cholesterol is available in the following dosage forms:

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

Niclosamide (ni-KLOE-sa-mide) belongs to the family of medicines called anthelmintics ( ant-hel-MIN-tiks) . Anthelmintics are medicines used in the treatment of worm infections.

Niclosamide is used to treat broad or fish tapeworm, dwarf tapeworm, and beef tapeworm infections. Niclosamide may also be used for other tapeworm infections as determined by your doctor. It will not work for other types of worm infections (for example, pinworms or roundworms).

Niclosamide works by killing tapeworms on contact. The killed worms are then passed in the stool. However, you may not notice them since they are sometimes destroyed in the intestine.

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

Oral
• Chewable tablets (U.S.)

Nicotinyl (nik-oh-TIN-ill) alcohol belongs to the group of medicines called vasodilators. Vasodilators increase the size of blood vessels and are used to treat problems resulting from poor blood circulation.

Nicotinyl alcohol is available without a prescription, in the following dosage form:

Oral
• Extended-release tablets (Canada)

Nitrates (NYE-trates) are used to treat the symptoms of angina (chest pain). Depending on the type of dosage form and how it is taken, nitrates are used to treat angina in three ways:

• to relieve an attack that is occurring by using the medicine when the attack begins;
• to prevent attacks from occurring by using the medicine just before an attack is expected to occur; or
• to reduce the number of attacks that occur by using the medicine regularly on a long-term basis.

When taken orally and swallowed, nitrates are used to reduce the number of angina attacks that occur. They do not act fast enough to relieve the pain of an angina attack.

Nitrates work by relaxing blood vessels and increasing the supply of blood and oxygen to the heart while reducing its work load.

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

The nitrates discussed here are available only with your doctor's prescription, in the following dosage forms:

Oral
• Isosorbide dinitrate
  • Extended-release capsules (U.S.)
  • Tablets (U.S. and Canada)
  • Chewable tablets (U.S.)
  • Extended-release tablets (U.S. and Canada)
• Isosorbide mononitrate
  • Extended-release tablets (U.S.)
  • Tablets (U.S.)
• Nitroglycerin
  • Extended-release capsules (U.S.)
  • Extended-release tablets (U.S. and Canada)

Nitrates ( NYE-trates) are used to treat the symptoms of angina (chest pain). Depending on the type of dosage form and how it is taken, nitrates are used to treat angina in three ways:

• to relieve an attack that is occurring by using the medicine when the attack begins;
• to prevent attacks from occurring by using the medicine just before an attack is expected to occur; or
• to reduce the number of attacks that occur by using the medicine regularly on a long-term basis.

When applied to the skin, nitrates are used to reduce the number of angina attacks that occur. The only nitrate available for this purpose is topical nitroglycerin (nye-troe-GLI-ser-in) .

Topical nitroglycerin is absorbed through the skin. It works by relaxing blood vessels and increasing the supply of blood and oxygen to the heart while reducing its work load. This helps prevent future angina attacks from occurring.

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

Nitroglycerin as discussed here is available only with your doctor's prescription, in the following dosage forms:

Topical
• Ointment (U.S. and Canada)
• Transdermal (stick-on) patch (U.S. and Canada)

Nylidrin (NYE-li-drin) belongs to the group of medicines called vasodilators. Vasodilators increase the size of blood vessels. Nylidrin is used to treat problems due to poor blood circulation.

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

Oral
• Tablets (Canada)

Nystatin (nye-STA-tin) belongs to the group of medicines called antifungals. Topical nystatin is used to treat some types of fungus infections of the skin.

Nystatin is available in the U.S. only with your doctor's prescription. It is available in Canada without a prescription; however, your doctor may have special instructions on the proper use of this medicine for your medical problem. Nystatin is available in the following dosage forms:

Topical
• Cream (U.S. and Canada)
• Ointment (U.S. and Canada)
• Topical powder (U.S. and Canada)

Nystatin and triamcinolone (nye-STAT-in and trye-am-SIN-oh-lone ) combination contains an antifungal and a corticosteroid (kor-ti-co-STER-oid) (cortisone-like medicine).

Antifungals are used to treat infections caused by a fungus. They work by killing the fungus or preventing its growth. This medicine will not work for other kinds of infections. Corticosteroids belong to the family of medicines called steroids. They are used to help relieve redness, swelling, itching, and other discomfort of many skin problems.

This medicine is used to treat certain fungus infections, such as Candida (Monilia), and to help relieve the discomfort of the infection.

Topical corticosteroids may rarely cause some serious side effects. Some of the side effects may be more likely to occur in children. Before using this medicine in children, be sure to talk to your doctor about these problems, as well as the good this medicine may do.

Nystatin and triamcinolone combination is available only with your doctor's prescription, in the following dosage forms:

Topical
• Cream (U.S.)
• Ointment (U.S.)

Nafarelin (NAF-a-re-lin ) is a hormone similar to the one normally released from the hypothalamus gland in the brain. It is used in the treatment of:

• Endometriosis, a painful condition caused by extra tissue similar to the lining of the uterus growing inside and outside of the uterus.
• Central precocious puberty (CPP), puberty developing too early in boys and girls.

When given regularly to boys and girls, this medicine helps to prevent them from continuing to develop the sexual features associated with puberty, slowing down the development of breasts in girls and the development of genital areas in boys and girls. This medicine delays puberty in a child only as long as the child continues to take it.

Nafarelin prevents the growth of tissue associated with endometriosis in adult women during treatment and for 6 months after treatment is discontinued. Reducing the amount of estrogen in the body is one way of treating endometriosis.

Suppressing estrogen can thin the bones or slow their growth. This is a problem for adult women whose bones are no longer growing like the bones of children. Slowing the growth of bones is a positive effect for girls and boys whose bones grow too fast when puberty begins too early. This is why nafarelin is used only for up to 6 months in adult women treated for endometriosis, but often is used for a longer time in girls and boys with pubertal problems. Boys and girls may benefit by adding inches to their adult height when nafarelin causes their bones to grow at a proper rate.

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

Nasal
• Solution (U.S. and Canada)

Nifurtimox (nye-FER-tim-oks) belongs to a group of medicines called antiprotozoals. It is used to treat an infection called American trypanosomiasis (Chagas' disease). Nifurtimox works by killing the protozoa (tiny, one-celled animals) that cause the infection.

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

Oral
• Tablets (Argentina and Germany)

Nefazodone (nef-AY-zoe-done ) is used to treat mental depression.

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

Oral
• Tablets (U.S.)

Naratriptan (NAR-a-trip-tan) is used to treat severe migraine headaches. Many people find that their headaches go away completely after they take naratriptan. Other people find that their headaches are much less painful, and that they are able to go back to their normal activities even though their headaches are not completely gone. Naratriptan often relieves symptoms that occur together with a migraine headache, such as nausea, vomiting, sensitivity to light, and sensitivity to sound.

Naratriptan is not an ordinary pain reliever. It should not be used to relieve any kind of pain other than migraine headaches.

Naratriptan may cause serious side effects in some people, especially people who have heart or blood vessel disease. Be sure that you discuss with your doctor the risks of using this medicine as well as the good that it can do.

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

Oral
• Tablets (U.S.)

Nevirapine ( ne-VYE-ra-peen) is used, with other medicines, in the treatment of the infection caused by the human immunodeficiency virus (HIV).

Nevirapine will not cure HIV infection or AIDS; however, it helps keep HIV from reproducing and appears to slow down the destruction of the immune system. This may help delay the development of problems usually related to AIDS or HIV disease. Nevirapine will not keep you from spreading HIV to other people. People who receive this medicine may continue to have other problems usually related to AIDS or HIV disease.

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

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

Nicotine ( NIK-oh-teen) in a nasal spray is used to help you stop smoking. It is used for up to 3 months as part of a stop-smoking program. This program may include counseling, education, or psychological support.

With the nasal spray, nicotine is inhaled through your nose and passes into your blood stream. This nicotine takes the place of the nicotine you would otherwise get from smoking. In this way, the withdrawal effects of not smoking are less severe. Then, as your body adjusts to not smoking, the use of nicotine nasal spray is decreased gradually over several weeks. Finally, use is stopped altogether.

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

Nasal
• Nasal spray (U.S.)

Nadroparin ( na-dro-PA-rin ) is used to prevent and treat deep vein thrombosis, a condition in which harmful blood clots form in the blood vessels of the legs. These blood clots can travel to the lungs and can become lodged in the blood vessels of the lungs, causing a condition called pulmonary embolism. Nadroparin is used for several days after surgery, while you are unable to walk. Nadroparin also is used to prevent blood clots from forming during hemodialysis.

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

Parenteral
• Injection (Canada)

Nesiritide ( ni-SIR-i-tide) is used for patients who have severe congestive heart failure that has recently become worse. Nesiritide is for patients who are short of breath while at rest or with minimal activity.

This medicine is available only in the following dosage form:

Parenteral
• Injection (U.S.)

Nitisinone (ni-TIS-uh-none) is given along with a special diet to treat hereditary tyrosinemia, type 1. This disease is caused by too much tyrosine in the blood. It may cause damage to the liver, kidneys, eyes, skin, and nervous system. Treatment with nitisinone and diet may slow the disease, but it will not cure it.

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

Oral
• Capsules (U.S.)

Nitazoxanide ( nye-tah-ZOX-ah-nide) belongs to a group of medicines called antiprotozoals. It is used to treat diarrhea that is caused by certain types of protozoa (tiny, one-celled animals).

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

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