Cardura, tablets 2 mg 30 pcs

Cardura is a vasodilator.

Pharmacodynamics

Participation of doxazosin in patients with symptoms of BPH leads to significant improvement of urodynamic parameters and reduction of symptoms of the disease. This action of the drug is explained by selective blockade of alpha₁-adrenoreceptors located in stroma and capsule of prostate, bladder neck.

Doxazosin has been shown to be an effective blocker of subtype 1A alpha₁ adrenoreceptors, which represent approximately 70% of all subtypes, alpha₁ adrenoreceptors located in the prostate. This explains its action in patients with BPH.

The maintenance effect of treatment with doxazosin and its safety have been proven with long-term use of the drug (e.g., up to 48 months).

Arterial hypertension

The use of doxazosin in patients with arterial hypertension leads to a significant decrease in BP as a result of reduction of PPS. Appearance of this effect is associated with selective blockade of alpha₁-adrenoreceptors located in vascular network. When administered once daily, the clinically significant antihypertensive effect is maintained for 24 hours, BP decreases gradually; the maximum effect is usually observed 2-6 hours after oral administration. In patients with arterial hypertension BP during doxazosin treatment was similar in the supine and standing positions.

It was noted that in contrast to non-selective alpha₁-adreno-blockers, tolerance to the drug did not develop during long-term treatment with doxazosin. Increased plasma renin activity and tachycardia are infrequent during maintenance therapy.

Doxazosin has favorable effect on blood lipid profile, significantly increasing HDL to total cholesterol ratio and significantly decreasing total triglycerides and total cholesterol. In this regard, it has an advantage over diuretics and beta-adrenoblockers, which have no favorable effect on these parameters. Taking into account the established connection of arterial hypertension and blood lipid profile with CHD, normalization of BP and lipid concentration during doxazosin administration leads to decrease of CHD risk.

It was observed that doxazosin treatment resulted in regression of left ventricular hypertrophy, inhibition of platelet aggregation and enhancement of tissue plasminogen activator activity. In addition, doxazosin was found to increase insulin sensitivity in patients with impaired glucose tolerance.

Doxazosin has no metabolic side effects and can be used in patients with bronchial asthma, diabetes, left ventricular insufficiency and gout.

In vitro studies have demonstrated the antioxidant properties of 6′- and 7′- hydroxymetabolites of doxazosin at a concentration of 5 μmol.

In controlled clinical studies conducted in patients with arterial hypertension, treatment with doxazosin was accompanied by improvement of erectile function. In addition, patients treated with doxazosin had less recurrence of erectile dysfunction than patients treated with antihypertensives.

Pharmacokinetics

Doxazosin is well absorbed after oral administration at therapeutic doses; T_max in blood is reached after approximately 2 h.

Doxazosin is approximately 98% bound to plasma proteins.

The primary pathways of metabolism of doxazosin are O-demethylation and hydroxylation.

The plasma excretion is biphasic, with a final T_1/2 of 22 h, allowing the drug to be administered once daily. Doxazosin undergoes active biotransformation; only less than 5% of the dose is excreted unchanged.

Performance in Special Patient Groups

According to pharmacokinetic studies, the pharmacokinetics of the drug in elderly patients and patients with renal impairment do not differ significantly from those in younger patients with normal renal function.

There are limited data from patients with impaired hepatic function about the effects of drugs that can alter hepatic metabolism (e.g., cimetidine). In a clinical study in 12 patients with moderate hepatic impairment, a single use of doxazosin was accompanied by a 43% increase in AUC and a 40% decrease in true oral clearance. Caution should be exercised when prescribing doxazosin, as well as other drugs fully biotransformed in the liver, in patients with liver dysfunction (see “Cautions”).

Indications

Active ingredient

Composition

1 tablet contains:

The active ingredient:

doxazosin (in the form of mesylate) 2 mg.

Associates:

Starch glycolate sodium,

Microcrystalline cellulose,

How to take, the dosage

The drug may be prescribed to be taken both in the morning and in the evening.

In benign prostatic hyperplasia, the initial dose of Cardura is 1 mg once daily to minimize the possibility of postural hypotension and/or syncope (fainting). Depending on individual urodynamics and the presence of symptoms of BPH, the dose may be increased to 2 mg and then to 4 mg up to a maximum recommended dose of 8 mg. The recommended interval for increasing the dose is 1-2 weeks. The average recommended dose is 2-4 mg once daily.

In arterial hypertension, the dose of the drug varies from 1 to 16 mg/day. It is recommended to start treatment with 1 mg once daily for 1 or 2 weeks in order to minimize the possibility of developing postural hypotension and/or syncope (fainting). Over the next 1 or 2 weeks, the dose may be increased to 2 mg once daily. To achieve the desired BP reduction, if necessary, the daily dose should be increased gradually, observing even intervals, up to 4 mg, 8 mg and up to a maximum of 16 mg, depending on the severity of the patient’s reaction. The average dose is 2-4 mg once daily.

The pharmacokinetics of doxazosin in patients with renal impairment are not altered, and the drug itself does not aggravate the existing renal dysfunction, so in patients in this group Cardura is used in normal doses.

There is no need to adjust the dosing regimen when prescribing the drug in elderly patients.

There is no experience of using Cardura in children.

Interaction

The co-administration of Cardura with FDE type 5 inhibitors in some patients may lead to symptomatic hypotension.

The majority (98%) of doxazosin in blood plasma is bound to proteins. The results of human plasma in vitro studies indicate that doxazosin does not affect the binding to proteins of digoxin, warfarin, phenytoin or indomethacin. In clinical practice, Cardura has been used without any evidence of interaction with thiazide diuretics, furosemide, beta-adrenoblockers, NSAIDs, antibiotics, oral hypoglycemic agents, uricosuric agents and anticoagulants.

On a single use of Cardura at a dose of 1 mg/day for 4 days and concomitant administration of cimetidine at a dose of 400 mg 2 times/day a 10% increase in mean AUC values and a statistically insignificant increase in mean plasma C max and mean T 1/2 of doxazosin were observed. A similar 10% increase in mean AUC values of doxazosin on cimetidine administration is within the range of variability (27%) of mean AUC values for doxazosin compared to placebo.

Special Instructions

As with any alpha-adrenoblocker treatment (especially at the start of therapy), a very small percentage of patients have experienced postural hypotension manifested by dizziness and weakness or loss of consciousness (fainting). Before starting any alpha-adrenoblocker prescription, patients should be advised how to avoid the symptoms of postural hypotension. At the beginning of treatment with Cardura, the patient should be advised to exercise caution in case of weakness or dizziness.

Caution should be exercised when combining Cardura with phosphodiesterase type 5 inhibitors because this may cause symptomatic hypotension in some patients.

Caution should be exercised when prescribing Cardura, as well as other drugs that are completely biotransformed in the liver, to patients with impaired hepatic function, avoiding prescribing maximum doses.

The pharmacokinetics of doxazosin in patients with renal impairment are not altered, and the drug itself does not aggravate the existing renal impairment, so in patients in this group Cardura is used in normal doses.

When prescribing Cardura, it should be taken into account that the ability to drive and operate machinery may be impaired, especially at the beginning of treatment. Dizziness may occur.

Contraindications

Hypersensitivity (including to other quinazolines).

Side effects

DGID

According to controlled clinical studies, the same adverse reactions have been reported in patients with DPH as in patients with arterial hypertension.

The following adverse reactions have been reported in post-marketing use of the drug.

Hematopoietic and lymphatic system disorders: very rare – leukopenia, thrombocytopenia.

Hearing and vestibular system disorders: infrequent – tinnitus.

Visual organ: often – color perception disorders; infrequent – atonic iris syndrome.

Gastrointestinal disorders: frequently – abdominal pain, diarrhea, dyspepsia, dry oral mucosa; infrequently – flatulence, constipation, vomiting.

Liver: very rarely cholestasis, hepatitis, jaundice.

The immune system: very rare – anaphylactic reactions.

Laboratory measures: infrequent – weight gain; very rare – increase in liver transaminase activity.

Metabolic disorders: infrequent – anorexia.

Musculoskeletal system: infrequent – arthralgia, back pain, muscle cramps, muscle weakness, myalgia.

CNS and peripheral nervous system: often – paresthesia; infrequently – hypoesthesia, tremor.

Psychiatric disorders: often – agitation, anxiety, insomnia; rarely – depression.

Transureting system disorders: infrequent increased frequency of urination, polyuria, urinary incontinence; very rare – dysuria, hematuria, nicturia.

Reproductive system disorders: very rarely – gynecomastia, impotence, priapism; very rarely – retrograde ejaculation.

Respiratory system: often – shortness of breath, rhinitis; infrequent – cough, nasal bleeding; very rare – exacerbation of existing bronchospasm.

The skin: infrequent – alopecia, skin itching, skin rash, purpura; very rare – urticaria.

Systemic system disorders: infrequent – skin rush, significant decrease in blood pressure, postural hypotension.

Others: infrequent – pain of different localization.

Arterial hypertension

In controlled clinical trials of Cardura, the most common adverse reactions were postural (occasionally associated with syncope) or nonspecific, which included the reactions listed below.

Hearing and vestibular system disorders: frequently, vertigo.

Gastrointestinal disorders: often – nausea.

CNS and peripheral nervous system disorders: very often – dizziness, headache; often – postural dizziness (after the first dose a marked decrease in BP may occur, which may lead to orthostatic vertigo, in severe cases, especially with rapid transition from lying to standing or sitting position – to fainting), drowsiness.

Respiratory system: often – rhinitis.

Others: often – asthenia, swelling of the lower extremities, fatigue, weakness.

Overdose

Symptoms: marked BP decrease, sometimes accompanied by fainting.

Treatment: the patient should be immediately placed on his back and legs elevated; if necessary, symptomatic therapy should be carried out. Binding of doxazosin to plasma proteins is high, so dialysis is ineffective.

Similarities