How does Cardura work?
Cardura relaxes the blood vessels when indicated for hypertension, making blood flow easier and lowering blood pressure.
When indicated for benign prostate hyperplasia- Cardura relaxes the muscles in the prostate and some parts of the bladder. This relieves symptoms of benign prostate hyperplasia, including difficulty initiating a urine flow, increased urge to urinate, and a weak stream. These problems are common in men as they age. The prostate gland is positioned below the bladder. When some of its muscles are enlarged, the tube that drains urine gets obstructed. This can create a feeling of an incompletely emptied bladder. In addition, doxazosin does not shrink the prostate.
Cardura is available in the following dosages:
Extended-release tablets come in the following doses: 4mg and 8mg
The recommended dose for benign prostatic hyperplasia is 1mg daily and can be taken in the morning or the evening. The maximum recommended daily dose for benign prostatic hyperplasia is 8mg daily. The extended-release 4mg tablet can be recommended for benign prostatic hyperplasia.
For hypertension, 1mg daily is given at first. The maximum recommended daily dose for hypertension is 16mg based on the blood pressure feedback. You may be asked to monitor your blood pressure for 6 hours after taking your first dose.
For geriatric patients with hypertension, 0.5mg once daily dose is recommended.
How to take Cardura?
Cardura should be taken as prescribed.
Take Cardura with a glass of water at the same time every day. Cardura can be taken in the morning or the evening. You can take Cardura with or without food.
The usual dose is 1mg daily at first. However, you may be asked to increase this dose by your doctor after some weeks.
You must continue taking your tablets regularly, as advised by your doctor.
Swallow the tablet whole. Do not chew or crush.
When taking Cardura for high blood pressure, your doctor may advise you about your lifestyle and diet changes. This can include regular exercise and consuming fewer foods that are high in sodium. This may also include lipid and diabetes management and smoking cessation. In addition, for hypertension, your doctor may advise you to take Cardura with other anti-hypertensive medication to achieve optimal blood pressure control. However, hypertension has no symptoms in most cases, so keep taking Cardura as your doctor prescribes, even if you feel well.
For those taking Cardura for benign prostatic hyperplasia, it may take up to 2 weeks before you notice an improvement in your symptoms.
How to store Cardura?
Store Cardura at room temperature, away from heat and moisture. Do not store Cardura in the bathroom and keep it out of reach of children.
Symptoms of overdosing include:
Overdosage could lead to hypotension or low blood pressure. If you start experiencing symptoms of passing out or difficulty breathing, contact the poison control center or call 911 for immediate medical assistance.
Signs of an allergic reaction to the active ingredient of Cardura or any of its excipients include skin rash, difficulty breathing, and swelling of the face, tongue, or throat. Seek immediate medical attention in such instances.
Common side effects of Cardura include:
- The feeling of tiredness and weakness
- Difficulty breathing or shortness of breath
- Lower limb edema and swelling of the fingers
- Flu-like symptoms include fever, nasal blockage, and coughing
- Heartburn, stomach discomfort, and indigestion
- Dry mouth
- Increased urge to urinate, urinary tract infection, and cystitis
Less common side effects of Cardura include:
- Blurred vision
- Irregular heartbeat
- Lower back pain, joint or muscle pain
- Chest pain
- Constipation, diarrhea, vomiting, and gastroenteritis
- Painful urination or blood in the urine
- Sleep disturbance, agitation, tremor, and anxiety
- Change in appetite and weight
- Nose bleeds
- Skin rash
- Ringing in the ears
- Deranged liver tests
Consult your healthcare practitioner if you notice any of these side effects.
Serious side effects
You should stop taking Cardura and seek out immediate medical attention if you start to experience any of the following:
- Heart attack
- Weakness in your upper and lower limbs and difficulty speaking. These could be signs of a stroke.
- Cataract surgery- Intraoperative Floppy Iris Syndrome (IFIS) has been noted during cataract surgery in patients currently or previously on alpha 1 androgenic blocker. You should inform your eye doctor/ surgeon of any medication you are presently on or if you used to take Cardura or other medicines of the same class. Then, they would be able to make the necessary modifications during surgery.
- Prostate cancer- Benign prostate hyperplasia and prostate cancer often co-exist; therefore, prostate cancer should be ruled out before treating benign prostatic hyperplasia symptoms.
- Priapism- Doxazosin and drugs of the same class have been associated with painful and prolonged penile erection, not relieved by intercourse. If this happens, it must be treated immediately. If not, it may lead to permanent impotence.
Do not take Cardura if you have a hypersensitivity or allergy to doxazosin or medicines that belong to the same class.
The active ingredient in Cardura may cause a drop in blood pressure resulting in fainting or dizziness, usually 2 to 6 hours after taking it. This incidental risk is higher when you start this treatment or after your doctor increases your dose. You should avoid situations where you may get injured if you faint and monitor your blood pressure regularly using a blood pressure monitor. You may be recommended to take the first dose of Cardura at night to avoid such injuries. This will be ideal if your Cardura dose increases or if you resume taking it after you have stopped it or skipped some doses. You may feel dizzy when you wake up or stand from a lying position. Avoid standing for long or staying in high temperatures to reduce your chances of dizziness.
Alcohol or cannabis use may also make you dizzy; therefore, alcohol consumption should be limited when on Cardura. If you use cannabis and have been prescribed Cardura, speak to your doctor.
Cardura can affect your alertness; therefore, refrain from using machinery or driving until you feel you can do it safely.
Before undergoing surgery, advise your doctor or dentist that you take Cardura or if you have ever taken it.
While on Cardura, you may need to check your prostate regularly to monitor your progress and identify any relevant side effects.
If you stop taking Cardura for whatever reason and need to start retaking it, speak to your doctor before you do so, as you may need an adjustment in the initial dose.
Having gastrointestinal blockage may increase the side effects of doxazosin.
If you suffer from kidney disease, you may have increased sensitivity to the effects of Cardura.
If you suffer from liver disease, you may experience heightened side effects from doxazosin.
You should not take Cardura if you are nursing.
Before taking Cardura, discuss with your doctor if you are pregnant or think you might be.
Cardura should not be taken by anyone under the age of 18 years.
The following are some medications that may interact with doxazosin:
- Nefazodone- used to treat depression
- Indinavir, Ritonavir, nelfinavir- used in the treatment of HIV
- Clarithromycin, Telithromycin- Used to treat bacterial infections
- Ketoconazole, Itraconazole- Used to treat fungal infections
- Sildenafil, Tadalafil, and Vardenafil-used to treat erectile dysfunction
- Beta-blockers like timolol and propranolol- Used to treat your heart rate and lower blood pressure
- Nifedipine-used to treat hypertension and angina
Any medication used to treat elevated blood pressure may interact with or heighten the side effects of doxazosin.
Some cough and cold remedies can raise your blood pressure, as well as NSAIDs like ibuprofen and naproxen.
Advise your doctor of any prescription, over-the-counter, and herbal remedies you take.
The active ingredient found in Cardura is contraindicated in adults with:
- A known allergy or hypersensitivity to the doxazosin, any of the drugs belonging to the same class, or any of the excipients found in Cardura
- Blockage of the upper urinary tract, chronic urinary tract infection, and bladder stones
- Severe hepatic impairment
Before starting Cardura, you should inform your doctor if you have a history of heart conditions like congestive heart failure or heart attack in the past six months. You should also tell your doctor if you suffer from liver diseases and some eye problems, particularly glaucoma and cataracts.