Halobetasol is used to treat swelling, inflammation, and itching associated with skin conditions such as eczema, dermatitis, rashes, insect bites, poison ivy, and allergies.

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

Hydroxychloroquine is in a class of drugs called antimalarials. It is used to prevent and treat acute attacks of malaria. It is also used to treat discoid or systemic lupus erythematosus and rheumatoid arthritis in patients whose symptoms have not improved with other treatments.

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

Hydromorphone is used to relieve moderate to severe pain. It also may be used to decrease coughing.

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

Hydrocortisone, 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. Hydrocortisone 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.

Halcinonide is used to treat the itching, redness, dryness, crusting, scaling, inflammation, and discomfort of various skin conditions.

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

Hydrocortisone is available with or without a prescription. Low-strength preparations (0.5% or 1%) are used without a prescription for the temporary relief of (1) minor skin irritations, itching, and rashes caused by eczema, insect bites, poison ivy, poison oak, poison sumac, soaps, detergents, cosmetics, and jewelry; (2) itchy anal and rectal areas; and (3) itching and irritation of the scalp. It is also used to relieve the discomfort of mouth sores.

Hydrocortisone may be prescribed by your doctor to relieve the itching, redness, dryness, crusting, scaling, inflammation, and discomfort of various skin conditions; the inflammation of ulcerative colitis or proctitis; or the swelling and discomfort of hemorrhoids and other rectal problems.

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

Hydroxyzine is used to relieve the itching caused by allergies and to control the nausea and vomiting caused by various conditions, including motion sickness. It is also used for anxiety and to treat the symptoms of alcohol withdrawal.

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

Hyoscyamine is used to control symptoms associated with disorders of the gastrointestinal (GI) tract. It works by decreasing the motion of the stomach and intestines and the secretion of stomach fluids, including acid. Hyoscyamine is also used in the treatment of bladder spasms, peptic ulcer disease, diverticulitis, colic, irritable bowel syndrome, cystitis, and pancreatitis. Hyoscyamine may also be used to treat certain heart conditions, to control the symptoms of Parkinson's disease and rhinitis (runny nose), and to reduce excess saliva production.

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

Dihydroergotamine and ergotamine belong to the group of medicines known as ergot alkaloids. They are used to treat severe, throbbing headaches, such as migraine and cluster headaches. Dihydroergotamine and ergotamine are not ordinary pain relievers. They will not relieve any kind of pain other than throbbing headaches. Because these medicines can cause serious side effects, they are usually used for patients whose headaches are not relieved by acetaminophen, aspirin, or other pain relievers.

Dihydroergotamine and ergotamine may cause blood vessels in the body to constrict (become narrower). This effect can lead to serious side effects that are caused by a decrease in the flow of blood (blood circulation) to many parts of the body.

The caffeine present in many ergotamine-containing combinations helps ergotamine work better and faster by causing more of it to be quickly absorbed into the body. The belladonna alkaloids, dimenhydrinate, and diphenhydramine in some combinations help to relieve nausea and vomiting, which often occur together with the headaches. Dimenhydrinate, diphenhydramine, and pentobarbital also help the patient relax and even sleep. This also helps relieve headaches.

Dihydroergotamine is also used for other conditions, as determined by your doctor.

These medicines are available only with your doctor's prescription, in the following dosage forms:

Oral
• Ergotamine
  • Sublingual tablets (U.S.)
• Ergotamine and Caffeine
  • Tablets (U.S. and Canada)
• Ergotamine, Caffeine, and Dimenhydrinate
  • Capsules (Canada)
• Ergotamine, Caffeine, and Diphenhydramine
  • Capsules (Canada)

Parenteral
• Dihydroergotamine
  • Injection (U.S. and Canada)

Rectal
• Ergotamine and Caffeine
  • Suppositories (U.S. and Canada)
• Ergotamine, Caffeine, Belladonna Alkaloids, and Pentobarbital
  • Suppositories (U.S.)

Haemophilus b polysaccharide (hem-OFF-fil-us BEE pol-i-SAK-ka-ryd ) vaccine is an active immunizing agent used to prevent infection by Haemophilus influenzae type b (Hib) bacteria. The vaccine works by causing your body to produce its own protection (antibodies) against the disease.

The following information applies only to the Haemophilus b polysaccharide vaccine.

Infection by Haemophilus influenzae type b (Hib) bacteria can cause life-threatening illnesses, such as meningitis, which affects the brain; epiglottitis, which can cause death by suffocation; pericarditis, which affects the heart; pneumonia, which affects the lungs; and septic arthritis, which affects the bones and joints. Hib meningitis causes death in 5 to 10% of children who are infected. Also, approximately 30% of children who survive Hib meningitis are left with some type of serious permanent damage, such as mental retardation, deafness, epilepsy, or partial blindness.

Immunization against Hib is recommended for all children 24 months up to 5 years of age (i.e., up to the 5th birthday). In addition, immunization is recommended for children 18 to 24 months of age, especially:

• Children attending day-care facilities.
• Children with chronic illnesses associated with increased risk of Hib disease. These illnesses include asplenia, sickle cell disease, antibody deficiency syndromes, immunosuppression, and Hodgkin's disease.
• Children 18 to 24 months of age who have already had Hib disease. These children may get the disease again if they are not immunized. Children who developed Hib disease when 24 months of age or older do not need to be immunized, since most children in this age group will develop antibodies against the disease.
• Children with human immunodeficiency virus (HIV) infection or acquired immunodeficiency syndrome (AIDS).
• Children of certain racial groups, such as American Indian and Alaskan Eskimo. Children in these groups seem to be at increased risk of Hib disease.
• Children living close together with groups of other persons. Close living conditions increase a child's risk of being exposed to persons who have Hib infection or who carry the bacteria.

It is recommended that children immunized when they were 18 to 24 months of age receive a second dose of vaccine, since these children may not produce enough antibodies to fully protect them from Hib disease. Children who were first immunized when they were 24 months of age or older do not need to be reimmunized.

This vaccine is available only from your doctor or other authorized health care professional, in the following dosage form:

Parenteral
• Injection

Heparin ( HEP-a-rin) is an anticoagulant. It is used to decrease the clotting ability of the blood and help prevent harmful clots from forming in the blood vessels. This medicine is sometimes called a blood thinner, although it does not actually thin the blood. Heparin will not dissolve blood clots that have already formed, but it may prevent the clots from becoming larger and causing more serious problems.

Heparin is often used as a treatment for certain blood vessel, heart, and lung conditions. Heparin is also used to prevent blood clotting during open-heart surgery, bypass surgery, and dialysis. It is also used in low doses to prevent the formation of blood clots in certain patients, especially those who must have certain types of surgery or who must remain in bed for a long time.

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

Parenteral
• Injection (U.S. and Canada)

Histamine (HISS-ta-meen) is used to help diagnose problems or disease of the stomach. This test determines how much acid your stomach produces.

How the stomach test is done: Before this medicine is given, the stomach contents are emptied through a tube. Then the dose of histamine, which is based on body weight, is injected under the skin. Five minutes later, the stomach contents are emptied and tested for acidity. This procedure may be repeated several times. An antihistamine medicine may be given before the histamine is injected to prevent a possible unwanted effect.

Histamine is to be used only under the supervision of a doctor. It is available in the following dosage form:

Parenteral
• Injection (Canada)

Atorvastatin, cerivastatin

Hydralazine and hydrochlorothiazide (hye-DRAL-a-zeen and hye-droe-klor-oh-THYE-a-zide) combination 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 also may increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.

Hydralazine works by relaxing blood vessels and increasing the supply of blood and oxygen to the heart while reducing its workload. The hydrochlorothiazide is a type of medicine known as a thiazide diuretic and helps reduce the amount of water in the body by acting on the kidneys to increase the flow of urine.

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

Oral
• Capsules (U.S.)

Hydroxypropyl cellulose ( hye-drox-ee-PROE-pil SELL-yoo-lose) belongs to the group of medicines known as artificial tears. It is inserted in the eye to relieve dryness and irritation caused by reduced tear flow that occurs in certain eye diseases.

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

Ophthalmic
• Ocular system (eye system) (U.S. and Canada)

Hydroxyurea ( hye-DROX-ee-yoo-REE-ah) belongs to the group of medicines called antimetabolites. It is used to treat some kinds of cancer and to prevent painful episodes associated with sickle cell anemia.

Hydroxyurea 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 hydroxyurea, 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.

When used in sickle cell anemia, hydroxyurea appears to increase the flexibility of sickled cells.

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

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

Oral
• Capsules (U.S. and Canada)

Hepatitis (hep-ah-TY-tiss) A is a serious disease of the liver that can cause death. It is caused by the hepatitis A virus (HAV), and is spread most often through infected food or water. Hepatitis A may also be spread by close person-to-person contact with infected persons (such as between persons living in the same household). Although some infected persons do not appear to be sick, they are still able to spread the virus to others.

Hepatitis A is less common in the U.S. and other areas of the world that have a higher level of sanitation and good water and sewage (waste) systems. However, it is a significant health problem in parts of the world that do not have such systems. If you are traveling to certain countries or remote (out-of-the-way) areas, hepatitis A vaccine will help protect you from hepatitis A disease.

It is recommended that persons 2 years of age and older be vaccinated with hepatitis A vaccine when traveling to the following parts of the world:

• Africa.
• Asia (except Japan).
• parts of the Caribbean.
• Central and South America.
• eastern Europe.
• the Mediterranean basin.
• the Middle East.
• Mexico.

Hepatitis A vaccine is also recommended for all persons 2 years of age and older who live in areas that have frequent outbreaks of hepatitis A disease or who may be at increased risk of infection from hepatitis A virus. These persons include:

• Military personnel.
• Persons living in or moving to areas that have a high rate of HAV infection.
• Persons who may be exposed to the hepatitis A virus repeatedly due to a high rate of hepatitis A disease, such as Alaskan Eskimos and Native Americans.
• Persons engaging in high-risk sexual activity, such as homosexual and bisexual males.
• Persons who use illegal injectable drugs.
• Persons living in a community experiencing an outbreak of hepatitis A.
• Persons working in facilities for the mentally retarded.
• Employees of child day-care centers.
• Persons who work with hepatitis A virus in the laboratory.
• Persons who handle primate animals.
• Persons with hemophilia.
• Food handlers.
• Persons with chronic liver disease.

Hepatitis A vaccine 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. and Canada)

Hyaluronate (hye-a-loo-ROE-nate ) is similar to a substance that occurs naturally in joints and that helps joints work properly by acting like a lubricant and shock absorber. This medicine is injected directly into the knee to relieve pain caused by osteoarthritis.

This medicine 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.)

Hydrocodone and ibuprofen ( hye-droe-KOE-done and eye-byoo-PROE-fen) combination is used to relieve pain.

The hydrocodone is a narcotic analgesic that acts in the central nervous system to relieve pain. If hydrocodone 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. Since hydrocodone and ibuprofen combination is only used for short-term (10 days or less) relief of pain, physical dependence will probably not occur.

Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) used in this combination to relieve inflammation, swelling, and pain.

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

Oral
• Tablets (U.S.)

Hepatitis (hep-ah-TY-tiss) A virus vaccine inactivated and hepatitis B virus vaccine recombinant is used to prevent infection caused by Hepatitis A and Hepatitis B in patients 18 years of age or older. The vaccine works by causing your body to produce its own protection (antibodies) against the disease. Hepatitis A and Hepatitis B are highly contagious, serious diseases of the liver.

The hepatitis A virus (HAV) is spread most often through infected food or water. Hepatitis A may also be spread by close person-to-person contact with infected persons (such as between persons living in the same household). Although some infected persons do not appear to be sick, they are still able to spread the virus to others.

Hepatitis A is less common in the U.S. and other areas of the world that have a higher level of sanitation and good water and sewage (waste) systems. However, it is a significant health problem in parts of the world that do not have such systems. If you are traveling to certain countries or remote (out-of-the-way) areas, hepatitis A vaccine will help protect you from hepatitis A disease.

Hepatitis B (HBV) is spread by contact with body fluids, such as blood, saliva, semen, or vaginal fluids; by needle sticks or sharing needles; or from mother to child.

Hepatitis A and Hepatitis B combination vaccine is recommended for all persons 18 years of age or older who are at risk from infection from their jobs or some behaviors, or from traveling to the following parts of the world:

• Africa.
• the Caribbean.
• Central and South America.
• Eastern and southern Europe.
• the Middle East.
• South and southeast Asia (except Japan).
• the Soviet Union (former).

Hepatitis A and Hepatitis B combination vaccine is also recommended for:

• Military personnel.
• Persons living in or moving to areas that have a high rate of HAV infection and who are at a high risk of HBV infection.
• Persons engaging in high-risk sexual activity, such as homosexual and bisexual males.
• Persons who use illegal injectable drugs.
• Persons at risk through their work, such as laboratory workers who handle live hepatitis A and hepatitis B virus, police and those who give first aid or medical help, and workers who come in contact with stool or sewage.
• People who work in child day-care centers and correctional facilities, residents of drug and alcohol treatment centers, and patients and staff in hemodialysis units.
• Patients who frequently receive blood and blood products, including those people who have problems with clotting, such as hemophiliacs.
• Persons with chronic liver disease.
• Healthcare workers who give first aid or emergency medical care.
• People who are at increased risk for HBV infection and who are in close contact with patients that have hepatitis A or B.

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

Parenteral
• Injection (U.S.)

Hydroxyamphetamine and Tropicamide ( hi-DROX-ee-am-fet-uh-meen and troe-PIK-a-mide ) is medicine that is put into your eye to make your pupil larger. It also reduces your body's ability to adjust your eye for near vision. These drops are used when you have your eyes examined by the eye doctor.

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

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