Doxazosin is the common name for the prescription drug Cardura, which is used to treat high blood pressure (hypertension) and symptoms of benign prostatic hyperplasia or BPH (enlarged prostate).
Doxazosin belongs to a class of drugs known as alpha-blockers.
It lowers blood pressure by relaxing the blood vessels, so blood can flow more freely, and it helps alleviate the symptoms of an enlarged prostate, relaxing the muscles of the bladder and prostate, which improves the urinary flow.
Doctors can also prescribe doxazosin to treat kidney stones, bladder problems in women.
Doxazosin was approved by the Food and Drug Administration in 2005, manufactured and sold by Pfizer, Inc. under the trademark Cardura.
Some manufacturers also offer generic versions of the drug.
Doxazosin is supplied in the form of a tablet or tablet with sustained release, which must be taken orally. Your doctor will probably start with a low dose and gradually increase it.
This medicine controls the symptoms, but does not cure any diseases. You should continue to take doxazosin even if you are feeling well.
Your blood pressure or prostate will need to be checked frequently while you are taking doxazosin, so you should visit your doctor regularly.
Doxazosin lowers blood pressure and can cause fainting or dizziness, especially when you first start taking it. You must warn your doctor if you experience severe dizziness or fainting.
The medication can also worsen thinking or reaction. Be careful when driving or performing other actions that require vigilance.
Doxazosin and pregnancy
It is not known whether doxazosin will harm an unborn baby. You should tell your doctor if you are pregnant or can become pregnant while taking this medication.
It is also unknown whether the drug passes into breast milk and whether it can harm breastfeeding.
Side effects of doxazosin
Some common, less serious side effects may include:
- Light Dizziness
- Runny nose
- Weight gain
- Feeling tired or drowsy
Elderly people may be more sensitive to the side effects of doxazosin, which may increase the risk of falling.
Serious side effects
Serious side effects of doxazosin may include:
- Symptoms of an allergic reaction
- Severe palpitations
- Labored breathing
- Swelling in the ankles, hands or feet
- Changes in vision
- Slurred speech
- An erection that is painful and lasts longer than 4 hours
You should immediately seek medical help if you have a serious side effect.
Some drugs that can interact with doxazosin include:
- Drugs associated with erectile dysfunction, including sildenafil (Viagra, Revatio), tadalafil (Cialis) and vardenafil (Levitra)
- Hepatitis C protease inhibitor (boceprevir)
- Monoamine oxidase (MAOI) inhibitors such as phenolsin (Nardil) and tranylcypromine (Parnate)
You must tell your doctor about all the medications that you take.
Doxazosin and alcohol
Drinking alcohol can cause certain side effects of doxazosin, so you should limit its consumption.
Do not drive, do not perform other actions that require you to be vigilant until you are sure that you can do it safely.
A typical dose for adults with high blood pressure
Initial dose: 1 milligram (mg), once a day before bedtime
Maintenance dose: 1 mg to 16 mg, once daily
A typical dose for adults with an enlarged prostate
Immediate release: 1 milligram (mg), once a day before bedtime
Prolonged action: 4 mg, once a day with breakfast
Immediate release: 1 mg to 8 mg, once a day before bedtime
Overdose with doxazosin
Symptoms of overdose may include severe dizziness or fainting.
If you suspect an overdose, you should immediately contact a toxicology center or an emergency room.
The missed dose of doxazosin
If you miss a dose of doxazosin, take it as soon as you remember.
However, skip it if it’s time for the next dose.
Do not take additional medication to make up for the missed dose.
If you miss a scheduled dose within a few days, consult your doctor before you start taking your medication again.