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THE MERCK MANUAL MEDICAL LIBRARY: The Merck Manual of Medical Information--Home Edition
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Pr

Prader-Willi syndrome

When Part of a Chromosome Is MissingSidebar

  • information resources on

  • Pa - Ps

    Pralidoxime

    Insecticide Poisoning: Diagnosis and Treatment

    Pramipexole

    Parkinson's Disease: Other Drugs
    Drugs Used to Treat Parkinson's DiseaseTables

    Pravastatin

    Lipid-Lowering DrugsTables

    Prazosin

    Some Drugs Used to Treat Urinary IncontinenceTables

    Precocious puberty

    Vaginal Bleeding (Abnormal)
    When Puberty Starts Too EarlySidebar

    Prednisolone

    see Corticosteroids; Prednisone

    Prednisone

    see also Corticosteroids

  • adrenal gland suppression by

  • Suppression of Adrenal Function by CorticosteroidsSidebar

  • in allergic bronchopulmonary aspergillosis

  • Allergic Bronchopulmonary Aspergillosis: Treatment

  • in autoimmune disorders

  • Autoimmune Disorders: Treatment

  • in autoimmune hemolytic anemia

  • Autoimmune Hemolytic Anemia: Treatment

  • in Behçet's syndrome

  • Behçet's Syndrome: Diagnosis and Treatment

  • in Bell's palsy

  • Bell's Palsy: Treatment and Prognosis

  • in Crohn's disease

  • Crohn's Disease: Anti-inflammatory Drugs
    Drugs That Reduce Bowel InflammationTables

  • in dermatomyositis

  • Polymyositis and Dermatomyositis: Treatment and Prognosis

  • in eosinophilic pneumonia

  • Eosinophilic Pneumonia: Prognosis and Treatment

  • in gout

  • Gout: Relieving the Acute Attack
    Drugs Used to Treat GoutTables

  • in idiopathic pulmonary fibrosis

  • Idiopathic Pulmonary Fibrosis: Treatment and Prognosis

  • in meningitis

  • Acute Bacterial Meningitis: Treatment and Prognosis

  • in multiple sclerosis

  • Multiple Sclerosis (MS): Treatment

  • in muscular dystrophy

  • Duchenne and Becker Muscular Dystrophies: Treatment

  • in osteopetroses

  • Osteopetroses: Treatment and Prognosis

  • in polyarteritis nodosa

  • Polyarteritis Nodosa: Diagnosis and Treatment

  • in polymyalgia rheumatica

  • Polymyalgia Rheumatica (PMR): Treatment

  • in polymyositis

  • Polymyositis and Dermatomyositis: Treatment and Prognosis

  • in rheumatoid arthritis

  • Drugs Used to Treat Rheumatoid ArthritisTables
    Rheumatoid Arthritis (RA): Corticosteroids

  • in systemic lupus erythematosus

  • Systemic Lupus Erythematosus (SLE): Prognosis and Treatment

  • in temporal (giant cell) arteritis

  • Temporal Arteritis: Diagnosis and Treatment

  • in transplantation

  • Drugs Used to Prevent Transplant RejectionTables

  • in ulcerative colitis

  • Ulcerative Colitis: Anti-inflammatory Drugs
    Drugs That Reduce Bowel InflammationTables

    Preeclampsia

    Risk Factors That Develop During Pregnancy: Preeclampsia
    Drug Use During Pregnancy
    Problems Affecting the Woman: Preeclampsia

    Preferred provider organizations

    How Health Care Is Paid For: PPOs

    Pregnancy

    see also Embryo; Fetus
    Normal Pregnancy
    From Egg to EmbryoFigures
    Placenta and Embryo at 8 WeeksFigures
    Skin Rashes During PregnancySidebar
    Stages of PregnancyTables

  • ABO incompatibility in

  • What Is Hemolytic Disease of the Newborn?Sidebar

  • in adolescents

  • Contraception and Adolescent Pregnancy

  • after premature menopause

  • Premature Menopause: Treatment

  • age considerations in

  • Risk Factors Present Before Pregnancy: Physical Characteristics

  • Down syndrome and

  • Prenatal Diagnostic Testing: Chromosomal Abnormalities
    A Woman's Age and Her Risk of Having a Baby With a Chromosomal AbnormalityTables

  • alcohol use during

  • Alcohol: Symptoms and Complications
    Drug Use During Pregnancy: Alcohol

  • amniocentesis during

  • Prenatal Diagnostic Testing: Amniocentesis
    Detecting Abnormalities Before BirthFigures

  • anemia in

  • Physical Changes: Heart and Blood Flow
    Self-Care: Drugs and Dietary Supplements
    Risk Factors Present Before Pregnancy: Anemia
    Risk Factors That Develop During Pregnancy: Anemia

  • anticonvulsant use during

  • Seizure Disorders: Treatment
    Risk Factors Present Before Pregnancy: Seizure Disorders

  • appendicitis during

  • Risk Factors That Develop During Pregnancy: Disorders That Require Surgery

  • aspartame use during

  • Drug Use During Pregnancy: Aspartame

  • aspirin use during

  • Persistent Pulmonary Hypertension

  • asthma during

  • Risk Factors Present Before Pregnancy: Asthma

  • autoimmune disorders in

  • Risk Factors Present Before Pregnancy: Autoimmune Disorders

  • bleeding during

  • Risk Factors That Develop During Pregnancy: Pregnancy Complications
    Risk Factors That Develop During Pregnancy: Placenta Previa
    Risk Factors That Develop During Pregnancy: Placental Abruption (Abruptio Placentae)
    Miscarriage: Symptoms

  • caffeine consumption during

  • Drug Use During Pregnancy: Caffeine

  • cancer during

  • Risk Factors Present Before Pregnancy: Cancer

  • cardiomyopathy with

  • Risk Factors That Develop During Pregnancy: Peripartum Cardiomyopathy

  • cholestasis during

  • Risk Factors That Develop During Pregnancy: Pregnancy Complications

  • chorea in

  • Chorea, Athetosis, and Hemiballismus

  • chorionic villus sampling during

  • Prenatal Diagnostic Testing: Chorionic Villus Sampling
    Detecting Abnormalities Before BirthFigures

  • cocaine use during

  • Cocaine: Symptoms and Complications
    Risk Factors That Develop During Pregnancy: Drugs

  • complications of

  • Risk Factors That Develop During Pregnancy: Pregnancy Complications

  • cortical necrosis during

  • Renal Cortical Necrosis

  • cytomegalovirus infection during

  • Cytomegalovirus (CMV) Infection: Symptoms

  • dating of

  • When Is the Baby Due?Sidebar

  • detection of

  • Detecting and Dating a Pregnancy

  • diabetes mellitus during

  • Physical Changes: Hormones
    Risk Factors Present Before Pregnancy: Diabetes
    Risk Factors That Develop During Pregnancy: Gestational Diabetes
    Large for Gestational Age (LGA)

  • Down syndrome and

  • Prenatal Diagnostic Testing: Chromosomal Abnormalities
    A Woman's Age and Her Risk of Having a Baby With a Chromosomal AbnormalityTables

  • drug addiction during

  • Drug Use and Abuse: Drug Addiction

  • drug use in

  • Risk Factors: Pregnancy and Breastfeeding
    Precautions With Over-the-Counter Drugs: Pregnant and Breastfeeding Women
    Risk Factors That Develop During Pregnancy: Drugs
    Drug Use During Pregnancy
    How Drugs Cross the PlacentaFigures
    Categories of Risk for Drugs During PregnancyTables
    Some Drugs That Can Cause Problems During PregnancyTables

  • alcohol

  • Alcohol: Symptoms and Complications
    Drug Use During Pregnancy: Alcohol

  • cocaine

  • Cocaine: Symptoms and Complications
    Risk Factors That Develop During Pregnancy: Drugs

  • marijuana

  • Marijuana: Symptoms and Complications

  • opioid

  • Opioids: Symptoms and Complications
    Drug Use During Pregnancy: Opioids

  • eclampsia in

  • Risk Factors That Develop During Pregnancy: Preeclampsia

  • ectopic

  • Ectopic Pregnancy: A Mislocated PregnancyFigures

  • Ehlers-Danlos syndrome and

  • Ehlers-Danlos Syndrome

  • fatty liver of

  • Risk Factors That Develop During Pregnancy: Fatty Liver of Pregnancy

  • fertilization in

  • see Fertilization

  • fever during

  • Risk Factors That Develop During Pregnancy: Fevers

  • fibroids during

  • Fibroids: Symptoms

  • folic acid and

  • Folate: Symptoms
    Brain and Spinal Cord Defects: Neural Tube Defects
    Mental Retardation/Intellectual Disability: Prevention and Prognosis

  • gallstones during

  • Risk Factors Present Before Pregnancy: Liver and Gallbladder Disorders

  • genetic screening before

  • Genetic Screening

  • gingivitis during

  • Gingivitis: Gingivitis due to Pregnancy

  • Graves' disease in

  • Risk Factors Present Before Pregnancy: Autoimmune Disorders
    Thyroid Disorders: Hyperthyroidism

  • heart disease in

  • Risk Factors Present Before Pregnancy: Heart Disease

  • HELLP syndrome in

  • Risk Factors That Develop During Pregnancy: Preeclampsia

  • hepatitis during

  • Risk Factors Present Before Pregnancy: Liver and Gallbladder Disorders
    Specific Medical Conditions and Travel: Pregnancy

  • herpes gestationis in

  • Skin Rashes During PregnancySidebar

  • herpes simplex virus infection during

  • Herpes Simplex Virus Infections: Other Infections and Complications
    Risk Factors Present Before Pregnancy: Sexually Transmitted Diseases

  • high blood pressure during

  • Risk Factors Present Before Pregnancy: High Blood Pressure
    Drug Use During Pregnancy
    Problems Affecting the Woman: Preeclampsia

  • high-risk

  • Pregnancy at High-Risk

  • HIV infection during

  • Human Immunodeficiency Virus (HIV) Infection: Transmission of Infection
    Risk Factors Present Before Pregnancy: Sexually Transmitted Diseases
    Human Immunodeficiency Virus (HIV) Infection: Diagnosis

  • hydronephrosis during

  • Hydronephrosis: Causes

  • idiopathic thrombocytopenic purpura in

  • Risk Factors Present Before Pregnancy: Autoimmune Disorders

  • immunization during

  • Some Drugs That Can Cause Problems During PregnancyTables

  • indomethacin use during

  • Persistent Pulmonary Hypertension

  • infection during

  • Kidney Infection (Pyelonephritis): Causes
    Listeriosis: Symptoms and Diagnosis
    Risk Factors Present Before Pregnancy: Sexually Transmitted Diseases
    Risk Factors That Develop During Pregnancy: Infections
    Risk Factors That Develop During Pregnancy: Urinary Tract Infections
    Drug Use During Pregnancy: Illicit Drugs
    Birth Defects: Infections

  • information resources on

  • Ca - Cy
    Family Planning

  • iodine deficiency during

  • Iodine: Iodine Deficiency

  • iron supplementation during

  • Iron: Treatment
    Self-Care: Drugs and Dietary Supplements

  • IUD use and

  • Contraception: Possible Problems

  • kidney disorders in

  • Risk Factors Present Before Pregnancy: Kidney Disorders

  • listeriosis during

  • Listeriosis: Symptoms and Diagnosis

  • liver disease during

  • Risk Factors Present Before Pregnancy: Liver and Gallbladder Disorders

  • loss of

  • see Abortion; Miscarriage

  • malaria during

  • Specific Medical Conditions and Travel: Pregnancy

  • Marfan syndrome and

  • Marfan Syndrome

  • marijuana use during

  • Marijuana: Symptoms and Complications

  • mask of (melasma)

  • Melasma
    Physical Changes: Skin

  • medical care during

  • Medical Care

  • miscarriage of

  • see Miscarriage

  • molar

  • Hydatidiform Mole

  • myasthenia gravis in

  • Risk Factors Present Before Pregnancy: Autoimmune Disorders

  • nausea and vomiting during

  • Risk Factors That Develop During Pregnancy: Hyperemesis Gravidarum

  • nipple discharge during

  • Breast Disorders: Nipple Discharge

  • number of

  • Risk Factors Present Before Pregnancy: Problems in a Previous Pregnancy

  • oligohydramnios in

  • Risk Factors That Develop During Pregnancy: Problems With Amniotic Fluid

  • opioid use during

  • Opioids: Symptoms and Complications
    Drug Use During Pregnancy: Opioids

  • physical changes during

  • Physical Changes
    Skin Rashes During PregnancySidebar
    Stages of PregnancyTables

  • placental problems in

  • Risk Factors That Develop During Pregnancy: Pregnancy Complications
    Risk Factors That Develop During Pregnancy: Placenta Previa
    Problems With the PlacentaFigures

  • polyhydramnios in

  • Risk Factors That Develop During Pregnancy: Problems With Amniotic Fluid

  • postterm

  • Labor and Timing Problems: Postterm Pregnancy and Postmaturity

  • preeclampsia in

  • Risk Factors That Develop During Pregnancy: Preeclampsia
    Drug Use During Pregnancy
    Problems Affecting the Woman: Preeclampsia

  • prenatal testing for

  • Prenatal Diagnostic Testing
    Some Genetic Disorders That Can Be Detected Before BirthTables
    A Woman's Age and Her Risk of Having a Baby With a Chromosomal AbnormalityTables
    Interpreting Abnormal Alpha-Fetoprotein LevelsSidebar
    Detecting Abnormalities Before BirthFigures

  • prevention of

  • see Contraception and contraceptives; Oral contraceptives

  • previous pregnancies and

  • Risk Factors Present Before Pregnancy: Problems in a Previous Pregnancy

  • problems achieving (infertility)

  • Infertility

  • rape and

  • Rape: Evaluation

  • rheumatoid arthritis during

  • Risk Factors Present Before Pregnancy: Autoimmune Disorders

  • Rh incompatibility in

  • Abortion: Complications
    Prenatal Diagnostic Testing: Chorionic Villus Sampling
    Medical Care: First Examination
    Risk Factors That Develop During Pregnancy: Rh Incompatibility
    Hospital (What to Expect)
    What Is Hemolytic Disease of the Newborn?Sidebar

  • risk factors in

  • Pregnancy at High-Risk

  • rubella during

  • Rubella

  • seizures during

  • Risk Factors Present Before Pregnancy: Seizure Disorders

  • self-care during

  • Self-Care

  • sexually transmitted disease during

  • Risk Factors Present Before Pregnancy: Sexually Transmitted Diseases

  • sickle cell disease and

  • Risk Factors Present Before Pregnancy: Anemia

  • smoking during

  • Risk Factors That Develop During Pregnancy: Drugs
    Drug Use During Pregnancy: Cigarette (Tobacco) Smoking

  • stages of

  • Stages of PregnancyTables

  • surgery during

  • Risk Factors That Develop During Pregnancy: Disorders That Require Surgery

  • systemic lupus erythematosus and

  • Systemic Lupus Erythematosus (SLE): Prognosis and Treatment
    Risk Factors Present Before Pregnancy: Autoimmune Disorders

  • termination of

  • see Abortion; Miscarriage

  • thyroiditis after

  • Thyroiditis: Subacute Painless Thyroiditis

  • toxemia of (preeclampsia)

  • Risk Factors That Develop During Pregnancy: Preeclampsia
    Drug Use During Pregnancy
    Problems Affecting the Woman: Preeclampsia

  • toxoplasmosis during

  • Toxoplasmosis

  • travel during

  • Specific Medical Conditions and Travel: Pregnancy

  • tubal

  • Pelvic Inflammatory Disease (PID): Symptoms

  • ultrasonography during

  • Prenatal Diagnostic Testing: Ultrasonography
    Detecting Abnormalities Before BirthFigures
    Medical Care: Follow-up Examinations

  • umbilical cord blood sampling during

  • Prenatal Diagnostic Testing: Percutaneous Umbilical Blood Sampling

  • uterine fibroids in

  • Risk Factors Present Before Pregnancy: Fibroids

  • vaccination during

  • Some Drugs That Can Cause Problems During PregnancyTables

  • vitamin A during

  • Vitamin A: Symptoms, Diagnosis, and Treatment

  • weight gain in

  • Obesity: Causes

    Premacular fibrosis

    Macular Pucker

    Premature ejaculation

    Premature Ejaculation
    Learning to Delay EjaculationSidebar

    Premature infant

    see also Labor and delivery, preterm
    Labor and Timing Problems
    Prematurity
    Physical Features of a Premature NewbornSidebar

  • apnea in

  • Apnea of Prematurity

  • dehydration in

  • Aging's Effects

  • eye problems (retinopathy) in

  • Preventive Health Care Visits
    Retinopathy of Prematurity

  • infection in

  • Sepsis
    Some Infections of NewbornsTables

  • intestinal problems (necrotizing enterocolitis) in

  • Necrotizing Enterocolitis

  • lung development problems (bronchopulmonary dysplasia) in

  • Bronchopulmonary Dysplasia (BPD)

  • respiratory distress syndrome in

  • Respiratory Distress Syndrome

  • sepsis in

  • Sepsis

  • vitamin E deficiency in

  • Vitamin E: Symptoms, Diagnosis, and Treatment

    Premature labor

    see Labor and delivery, preterm

    Premature menopause

    Premature Menopause

    Premenstrual dysphoric disorder

    Premenstrual Syndrome (PMS)
    Premenstrual Syndrome (PMS): Treatment

    Premenstrual syndrome (PMS)

    Deciphering Medical Terms for Menstrual DisordersTables
    Premenstrual Syndrome (PMS)
    Symptoms of Premenstrual SyndromeSidebar

    Prenatal testing

    Prenatal Diagnostic Testing
    Some Genetic Disorders That Can Be Detected Before BirthTables
    A Woman's Age and Her Risk of Having a Baby With a Chromosomal AbnormalityTables
    Interpreting Abnormal Alpha-Fetoprotein LevelsSidebar
    Detecting Abnormalities Before BirthFigures
    Birth Defects: Diagnosis
    Chromosomal and Genetic Abnormalities
    Mental Retardation/Intellectual Disability: Prevention and Prognosis

    Presbycusis

    Changes in the Body: Ears
    Effects of Aging
    Hearing Loss and Deafness: Age

    Presbyesophagus

    Esophageal Disorders

    Presbyopia

    Changes in the Body: Eyes
    Effects of Aging
    Symptoms: Refractive Error
    Refractive Disorders: Causes

    Preschool

    Promoting Optimal Health and Development
    Childcare

    Prescription drugs

    see also Drugs
    Overview of Drugs: Prescription or Nonprescription

  • abuse of

  • Antianxiety Drugs and Sedatives
    Classifying the Abuse Potential of Prescription DrugsSidebar

    Preservatives, for food

    Food Allergy

    Pressure

  • bladder

  • Urinary Incontinence: Diagnosis

  • blood

  • see Blood pressure; High blood pressure; Low blood pressure

  • carbon dioxide

  • Blood Tests Tables

  • in diving

  • Diving and Compressed Air Injuries
    Breathing Air Under High PressureSidebar
    High Risk Factors for DivingSidebar

  • ear

  • Ears: Middle Ear
    Barotrauma
    The Eustachian Tube: Keeping Air Pressure EqualFigures
    Problems in Transit: Ear and Sinus Pressure

  • eye (intraocular)

  • anterior chamber paracentesis for

  • Hypertensive Retinopathy

  • increased (glaucoma)

  • Symptoms: Eye Pain
    Glaucoma
    Drugs Used to Treat GlaucomaTables

  • measurement of

  • Glaucoma: Screening and Diagnosis

  • oxygen

  • Blood Tests Tables

    Pressure sores

    Pressure Sores
    Common Sites for Pressure SoresFigures

  • casts and

  • Fractures: Rehabilitation and Prognosis