Cardura
Generic name: Doxazosin
Brand Name: Cardura
Indications
Doxazosin is used to treat hypertension (high blood pressure) and benign prostatic hyperplasia (BPH, enlarged prostate).
Doxazosin is in a group of drugs called alpha-adrenergic blockers. Doxazosin causes the blood vessels (veins and arteries) to relax and expand, improving blood flow. Doxazosin also relaxes muscles in the prostate and bladder neck, making it easier to urinate.
Dosage and Administration
Cardura is available as colored tablets for oral use and contains 1 mg (white), 2 mg (yellow), 4 mg (orange) and 8 mg (green) of doxazosin as the free base.
Normal Dosage:
Dosage Must Be Individualized: The initial dosage of doxazosin mesylate in patients with hypertension and/or BPH is 1 mg given once daily in the a.m. or p.m. This starting dose is intended to minimize the frequency of postural hypotension and first dose syncope associated with doxazosin mesylate
Benign Prostatic Hyperplasia :The initial dosage of doxazosin mesylate is 1 mg, given once daily in the a.m. or p.m. Depending on the individual patient's urodynamics and BPH symptomatology, dosage may then be increased to 2 mg and thereafter to 4 mg and 8 mg once daily, the maximum recommended dose for BPH. The recommended titration interval is 1-2 weeks. Blood pressure should be evaluated routinely in these patients.
Hypertension: The initial dosage of doxazosin mesylate is 1 mg given once daily. Depending on the individual patient's standing blood pressure response (based on measurements taken at 2-6 hours post-dose and 24 hours post-dose), dosage may then be increased to 2 mg and thereafter if necessary to 4 mg, 8 mg and 16 mg to achieve the desired reduction in blood pressure.
Overdose?
Symptoms of a doxazosin overdose may include drowsiness, fainting, or seizure (convulsions).
Drug Description
Doxazosin mesylate is a quinazoline compound that is a selective inhibitor of the alpha1 subtype of alpha adrenergic receptors. The chemical name of doxazosin mesylate is 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcarbonyl) piperazine methanesulfonate. The empirical formula for doxazosin mesylate is C23H25N5O5•CH4O3S and the molecular weight is 547.6. It has the following structure:
Cardura is freely soluble in dimethylsulfoxide, soluble in dimethylformamide, slightly soluble in methanol, ethanol, and water (0.8% at 25°C), and very slightly soluble in acetone and methylene chloride.
Side Effects
Most common side effects may include: dizziness, drowsiness, fatigue, and headache.
Less common side effects may include: Abdominal pain, abnormal vision, arthritis, constipation, depression, diarrhea, difficulty sleeping, dry mouth, eye pain, fluid retention, flu-like symptoms, flushing, gas, increased sweating, inability to hold urine or other urination problems, indigestion, inflammation of conjunctiva (pinkeye), itching, flushes, joint pain, lack of muscle coordination, low blood pressure, motion disorders, muscle cramps, muscle pain, muscle weakness, nasal stuffiness, nausea, nervousness, nosebleeds, pain, rash, ringing in ears, shortness of breath, thirst, tingling or pins and needles, weakness.
Rare side effects may include: Abnormal thinking, agitation, allergic reactions, altered sense of smell, amnesia, blood in the urine, breast development in men, breast pain, breathing difficulties, changeable emotions, changes in taste, chest pain, confusion, coughing, decreased sensation, dizziness when standing up, dry skin, earache, fainting, fecal incontinence, fever, frequent urination, gout, hair loss, heart attack, hives, inability to concentrate, inability to tolerate light, increased appetite, increased thirst, infection, loss of appetite, loss of sense of personal identity, migraine headache, morbid dreams, nighttime urination, pallor, prolonged erections, rapid pounding heartbeat, sexual problems, sinus inflammation, slight or partial paralysis, slow heartbeat, sore throat, stroke, tremors, twitching, urinary disorders, vomiting, weight gain, weight loss, wheezing, yellow skin and eyes.
Precautions
- Tell your doctor if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have prostate cancer, low blood pressure, kidney problems, or liver disorders
- Doxazosin can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.
- Avoid drinking alcohol, which can increase some of the side effects of doxazosin.
- Avoid using other medicines that make you sleepy (such as cold medicine, pain medication, muscle relaxers, and medicine for seizures, depression or anxiety). They can add to sleepiness caused by doxazosin.
Drug Interactions
Some medicines may interact with Cardura. Tell your health care provider if you are taking any of the following medicines.
- Cimetidine or verapamil because side effects such as dizziness and lightheadedness may occur.
- Phosphodiesterase type 5 inhibitors (eg, vardenafil) because severe low blood pressure may occur.
This may not be a complete list of all interactions that may occur. Ask your health care provider if this medicine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
