Alprostadil: A type of drug called a vasodilator — These drugs can increase blood flow by expanding blood vessels.

Antiarrythmics: Medicines used to treat abnormal rhythms in the heart

Antibiotics: Any of a class of medicines that kill infection-causing germs

Antidepressants: Medicines used to treat depression and other related conditions

Antihistamines: Medicines used to treat allergic reactions or allergies

Antihypertensives: Medicines used to treat high blood pressure

Anti-inflammatory drugs: Drugs that reduce inflammation (swelling) by modifying the body’s immune response

Anxiety: A feeling of apprehension, often characterized by feelings of stress

Arteriography: A test given to patients who are candidates for vascular reconstructive surgery — During this test, a dye is injected into the artery believed to be damaged so that the artery can be viewed by X-ray.

Atherosclerosis: Also called hardening of the arteries — This is a process in which the walls of the arteries become thickened and hardened, usually due to a buildup of fat deposits.

Bladder: The sac that holds urine

Bloody ejaculation: See hematospermia.

Cancer: A disease that occurs when abnormal cells in a part of the body divide and grow out of control

Cavernosography: A test used in conjunction with the dynamic infusion cavernosometry (see below) that involves a dye that is injected into the penis — The penis is then X-rayed and doctors are able to visualize a venous leak (see below).

Chemotherapy: The use of drugs whose main effect is either to kill or slow the growth of rapidly multiplying cells — It is often used in cancer treatment, and usually includes a combination of drugs.

Cialis®: The brand name of the drug tadalafil

Clinical trial: An organized research program conducted with patients to evaluate a new medical treatment, drug, or device

Complete blood count (CBC): A group of blood tests including hemoglobin concentration, red blood cell count, and white blood cell count

Corpora cavernosa: Two chambers in the penis that run the length of the organ and are filled with spongy tissue

Delayed ejaculation: An inability to ejaculate either during intercourse or with manual stimulation

Depression: A disorder characterized by feelings of extreme sadness, guilt, helplessness and hopelessness, and thoughts of death

Diagnosis: The process by which a doctor determines what disease a patient has by studying the patient’s symptoms and medical history, and analyzing any tests performed (blood tests, urine tests, brain scans, etc.)

Diuretic: Drugs that promote the formation of urine by the kidney

Duplex ultrasound: A penile test performed by bouncing soundwaves off tissue to determine penile blood flow

Dynamic infusion cavernosometry: A test during which fluid is pumped into the penis so doctors can determine the severity of a venous leak

Ejaculate: The fluid that is expelled from a man’s penis during sexual climax (orgasm)

Ejaculation: When sperm and other fluids come from the penis during sexual climax (orgasm)

Erectile dysfunction: The inability to develop or sustain an erection satisfactory for sexual activity

Erection: A state in which the penis fills with blood and becomes rigid

Glans: The head of the penis

Hematospermia: A disorder in which inflammation of the seminal vesicles, the colon, or the prostate causes a bloody ejaculation

Histamine H2 receptor antagonists: Medicines used to treat stomach ulcers that work by decreasing the amount of acid produced by the stomach

Hormones: Chemicals that stimulate or regulate the activity of cells or organs

Impotence: See Erectile dysfunction.

Infertility: The inability to conceive or produce offspring

Intercavernous injection therapy: Treatment for erectile dysfunction in which a medicine is injected directly into the penis

Intraurethral therapy: Treatment for erectile dysfunction in which a medicine, in suppository form, is inserted into the urethra

Levitra®: The brand name of the drug vardenafil

Libido: A person’s sex drive

Lipid profile: A blood test that measures the level of lipids (fats), such as cholesterol and triglycerides

Luteinizing hormone (LH): A hormone produced by the pituitary gland located at the base of the brain — In men, LH stimulates the production of testosterone, a hormone necessary for sperm production. In women, LH causes ovulation.

Meatus: The opening at the tip of the penis where urine and semen are discharged

MUSE: The brand name of the intraurethral form of the medicine alprostadil

Neurologist: A medical specialist with advanced training in the diagnosis and treatment of diseases of the brain, spinal cord, nerves, and muscles

Neurological disorders: Disorders that affect the brain, spinal cord, nerves, or muscles

Non-steroidal anti-inflammatory drugs (NSAIDs): Medicines used to treat inflammation of the body’s tissues

Nocturnal penile tumescence and rigidity testing: A test used to monitor erections that occur naturally during sleep — This test can help determine if a man’s erectile problems are due to physical or psychological causes.

Orgasm: Sexual climax

Parenteral: Taken into the body in a way other than the digestive tract, usually injected in a muscle or vein

Penile biothesiometry: A test that uses electromagnetic vibration to determine sensitivity and nerve function of the penis

Penile implant: An inflatable penile prosthesis surgically placed in the penis — It allows a man to have an erection whenever he chooses.

Penile injection: A medicine that is injected into the penis in order to produced an erection

Performance anxiety: When a person anticipates some sort of problem occurring during sex

Peyronie's disease: A condition in which a plaque, or hard lump, forms in the penis — The hardened plaque reduces flexibility, causing pain and forcing the penis to bend or arc during erection.

Pituitary gland: The main endocrine gland — It produces hormones that control other glands and many body functions including growth.

Premature ejaculation: Ejaculation that occurs sooner than a man wishes, usually before or soon after penetration

Priapism: A persistent, often painful erection that can last from several hours to a few days

Prostate cancer: The most common form of cancer in American men and the second leading cause of cancer death in men — Marked by abnormal growth of cells in the prostate.

Prosthesis: An artificial replacement of a part of the body

Retrograde ejaculation: A condition that occurs when, at orgasm, the ejaculate is forced back into the bladder rather than through the urethra and out the end of the penis

Rheumatologist: A doctor who specializes in disorders of the blood, blood vessels, and connective tissues

Scrotum: The sac of skin that surrounds the testicles

Semen: The fluid containing sperm (the male reproductive cells) that is expelled (ejaculated) through the end of the penis when the man reaches sexual climax (orgasm)

Seminal vesicles: The sac-like pouches that attach to the vas deferens near the base of the urinary bladder — The seminal vesicles produce a sugar-rich fluid called fructose that provides sperm with a source of energy that helps sperm move. The fluid of the seminal vesicles makes up most of the volume of a man’s ejaculatory fluid, or ejaculate.

Sex therapist: A professional counselor for people with sexual disorders

Sex therapy: Counseling for sexual disorders

Shaft of the penis: The long, slender cylinders of tissue inside the penis that contain spongy tissue and expand to produce erections

Sildenafil (Viagra®): A medicine used to treat erectile dysfunction that works by increasing the flow of blood into the penis

Sperm: The male reproductive cells

Suppository: A type of medicine designed to melt at body temperature within a body cavity other than the mouth

Tadalafil (Cialis®): A medicine used to treat erectile dysfunction that works by increasing the flow of blood into the penis

Testicles (testes; singular testis): Part of the male reproductive system — The testicles manufacture the male hormones, including testosterone, and produce sperm, the male reproductive cells. The testicles are located inside the scrotum, the loose sac of skin that hangs below the penis.

Testosterone: The male hormone that is essential for sperm production and the development of male characteristics, including muscle mass and strength, fat distribution, bone mass, and sex drive

Testosterone replacement therapy: Treatment in which the blood testosterone level is returned to the normal range based on the man's age — This is done by administering testosterone either by implantation under the skin, by mouth, with patches, or by injection.

Transurethral therapy: Treatment for erectile dysfunction performed through or by way of the urethra

Tranquilzer: A medicine that relieves anxiety

Tunica alburginea: The membrane surrounding the corpora cavernosa

Ultrasound: A test during which a special device takes a "picture" of the body’s tissues using high-frequency sound waves

Urethra: The tube that carries urine from the bladder to outside of the body

Urinalysis: An analysis of the urine

Urologist: A doctor who is specially trained to treat problems of the male and female urinary system, and the male sex organs

Vacuum constriction device: A device in which pumped air out of a cylinder creates a vacuum, drawing blood into the shaft of the penis and causing it to swell and become erect

Vardenafil (Levitra®) A medicine used to treat erectile dysfunction that works by increasing the flow of blood into the penis

Vas deferens: The long, muscular tube that travels from the epididymis into the pelvic cavity, to just behind the urinary bladder — The vas deferens transports mature sperm to the urethra in preparation for ejaculation.

Vascular disease: A disease of the blood vessels

Vascular reconstructive surgery: Surgery performed in an attempt to improve the flow of blood

Vasoactive injection: A test during which an erection is produced by injecting special solutions that cause the blood vessels to dilate

Venous leak: When the veins in the penis cannot prevent blood from leaving the penis during erection, preventing the erection from being maintained

Venous ligation: A procedure during which veins are bound or removed, enabling an adequate amount of blood supply

Viagra®: The brand name of the medicine sildenafil