Health Library

Plain-language explanations of common health topics, backed by trusted U.S. government medical sources.

Conditions

What Is High Blood Pressure?When the force of blood in your arteries stays too high.What Is Diabetes?A condition where blood sugar levels run too high.What Causes Erectile Dysfunction?Trouble getting or keeping an erection, and common causes.What Does High Cholesterol Mean?What your cholesterol numbers mean for your heart.What Is Sciatica?Nerve pain that runs from your lower back down a leg.What Is Atrial Fibrillation?An irregular, often fast heartbeat and why it matters.What Is Eczema?Dry, itchy, inflamed skin and how it's managed.What is duplicity for What causes gout?Sudden joint pain from uric acid crystals, often in the big toe.

Medications

Metformin Side EffectsCommon side effects of this diabetes medicine.Sildenafil Side EffectsWhat to expect and watch for with sildenafil (Viagra).

Tests & Procedures

What Is Testosterone?The main male hormone and what levels can mean.What Is a Normal Blood Sugar?The healthy range for blood sugar readings.What Is an MRI?A painless scan that makes detailed pictures inside your body.

Wellness

How Much Water Should I Drink?Simple daily hydration guidance for most adults.How Much Exercise Do I Need?How much weekly activity keeps you healthy.Healthy Eating BasicsEasy, everyday tips for a balanced diet.How Much Sleep Do I Need?How many hours of sleep adults really need.Which Vaccines Do Adults Need?The routine vaccines recommended for adults.