Brand & Generic Names
Basic Information
- Habit forming? No
- Prescription needed? Yes
- Available as generic? No
- Drug class: Antihypertensive
Uses
Treats high blood pressure.
Dosage & Usage Information
How to take:
Tablet--Swallow with liquid or food to lessen stomach
irritation. If you can't swallow whole, crumble tablet and take
with liquid or food.
When to take:
Once a day (usually) at bedtime.
If you forget a dose:
Take as soon as you remember. Don't ever
double the dose.
What drug does:
Relaxes smooth muscle in arteries, reducing blood pressure.
Terazosin doesn't cure hypertension, but controls it. Persons
with hypertension may need lifelong treatment.
Time lapse before drug works:
15 minutes.
Don't take with:
Any other drug (especially over-the-counter medicines containing alcohol) without consulting your doctor.
Overdose
SYMPTOMS:
Difficult breathing, vomiting, fainting, slow
heartbeat, coma, diminished reflexes.
WHAT TO DO:
- Dial 911 (emergency) or O (operator) for an ambulance or
medical help. Then give first aid immediately.
- If patient is unconscious and not breathing, give mouth-to-
mouth breathing. If there is no heartbeat, use cardiac massage
and mouth-to-mouth breathing (CPR). Don't try to make patient
vomit. If you can't get help quickly, take patient to nearest
emergency facility.
- See EMERGENCY Information.
Possible Adverse Reactions or Side Effects
Life-threatening:
In case of overdose, see Overdose Section.
Common:
Headache, dizziness,
tiredness or weakness.
Infrequent:
- Chest pain;
lightheadedness on
arising from bed or
chair (more likely to
occur with first dose);
increased or rapid
heartbeat, fainting,
nausea and vomiting.
- Fluid retention and
weight gain.
Rare:
Back pain, joint pain,
blurred vision,
stuffy nose,
drowsiness.
Warnings & Precautions
Don't take if:
- You are allergic to any alpha-adrenergic blocker*.
- You are under age 12.
Before you start, consult your doctor:
- If you will have surgery within 2 months, including dental
surgery, requiring general or spinal anesthesia.
- If you have heart disease or chronic kidney disease.
- If you have a peripheral circulation disorder (intermittent
claudication, Buerger's disease).
- If you have history of depression.
Over age 60:
More sensitivity to drug causing weakness, fainting episodes,
low temperature.
Pregnancy:
Studies inconclusive on harm to unborn child. Decide with your
doctor whether drug benefits justify risk to unborn child.
Breast-feeding:
No proven problems. Consult doctor.
Infants & children:
Not recommended for children. Adequate studies not complete.
Prolonged use:
Talk to your doctor about the need for follow-up medical
examinations or laboratory studies.
Skin & sunlight:
No problems expected.
Driving, piloting or hazardous work:
Don't drive or pilot aircraft until you learn how medicine
affects you. Don't work around dangerous machinery. Don't climb
ladders or work in high places. Danger increases if you drink
alcohol or take medicine affecting alertness and reflexes, such
as antihistamines, tranquilizers, sedatives, pain medicine,
narcotics and mind-altering drugs.
Discontinuing:
- Don't discontinue without consulting doctor. Dose may require
gradual reduction if you have taken drug for a long time. Doses
of other drugs may also require adjustment.
- Stopping abruptly may cause rebound high blood pressure,
anxiety, chest pain, insomnia, headache, nausea, irregular
heartbeat, flushed face, sweating.
Others:
- Avoid becoming overheated.
- Check blood pressure frequently.
- May affect results in some medical tests.
Possible Interaction with Other Drugs
GENERIC NAME |
COMBINED EFFECT |
| |
------------------------ |
----------------------- |
Diclofenac |
Decreases effectiveness of |
|
terazosin. Causes sodium and fluid |
|
retention. |
Diuretics, loop* |
Decreased effectiveness of |
|
terazosin. |
Estrogens* |
Decreases effectiveness of |
|
terazosin. |
Lisinopril |
Increased antihypertensive effect. |
|
Dosage of each may require |
|
adjustment. |
Nicardipine |
Blood pressure drop. Dosages may |
|
require adjustment. |
Nimodipine |
Dangerous blood pressure drop. |
Non-steroidal |
Decreases effectiveness |
anti-inflammatory |
of terazosin. Causes sodium and |
drugs (NSAIDs)* |
fluid retention. |
Other medicines to |
Decreases effectiveness of |
treat high blood |
terazosin. |
| |
| |
Sympathomimetics* |
Decreases effectiveness of |
|
terazosin. |
Possible Interaction with Other Substances
INTERACTS WITH |
COMBINED EFFECT |
--------------- |
--------------- |
Alcohol: |
Increased sensitivity to sedative |
|
effect of alcohol and very low |
|
blood pressure. Avoid. |
| |
| |
Caffeine drinks. |
Decreased terazosin effect. |
| |
Cocaine: |
Blood pressure rise. Avoid. |
| |
Foods: |
No problems expected. |
| |
Marijuana: |
Weakness on standing. |
| |
Tobacco: |
No problems expected. |
|