Alfuprost MR, 10 mg 30 pcs.

Pharmacodynamics

Alfuzosin is a quinazoline derivative active when taken orally. It is a selective antagonist of postsynaptic alpha₁ adrenoreceptors.

In vitro pharmacological tests have shown selective action of alfuzosin on alpha₁ receptors located in the prostate, at the bottom of the bladder and in the prostatic portion of the urethra. As a result of direct action on the smooth muscle of prostate tissue, alpha-₁-adrenoblockers reduce resistance to urine outflow.

Alfuzosin improves urinary parameters by reducing urethral tone and resistance to outflow from the bladder, facilitating bladder emptying. Administration of alfuzosin in patients with benign prostatic hyperplasia is achieved:

• significant increase in maximum flow rate (Q_max) by an average of 30% in patients with Q_max ≤ 15 ml/s. This improvement was observed beginning with the first dose;
• significant decrease in resistance to urine flow and increase in urine excretory volume;
• significant decrease in residual urine volume.

Pharmacokinetics

absorption: The mean relative bioavailability is 104.4% compared with the immediate-release form (2.5 mg twice daily) in healthy middle-aged volunteers, and maximum plasma concentration is reached 9 hours after alfuzosin administration, compared with 1 hour for the immediate-release form.

The half-life of alfuzosin is 9.1 hours. Studies have shown that the area under the concentration-time curve when alfuzosin is taken after meals is comparable to the results when alfuzosin is taken before meals, hence food intake does not affect the pharmacokinetic profile of the drug. Compared with healthy middle-aged volunteers, pharmacokinetic parameters are not increased in elderly patients.

In comparison with individuals with normal renal function, the mean values of maximum concentration area under the concentration-time curve are moderately increased in patients with renal insufficiency, with no change in the elimination half-life. This change in the pharmacokinetic profile of alfuzosin is not considered to be of clinical significance, so it does not require dose adjustment.

Metabolism: Binding of alfuzosin to plasma proteins is about 90%. Alfuzosin is almost completely metabolized in the liver.

Elimination: only 11% of alfuzosin unchanged is found in the urine. Most metabolites (which have no activity) are excreted with feces (75-90%).
Pharmacokinetic profile of alfuzosin does not change in chronic heart failure.

Indications

Treatment of functional disorders of urination in benign prostatic hyperplasia.

Active ingredient

How to take, the dosage

Internal.
The recommended dose is: 1 tablet of Alfuprost MR daily after meals. The tablets should be taken as a whole.

Interaction

Unrecommended combinations:

With alpha1-receptor blockers (prazosin, urapidil, minoxidil): increasing the hypotensive effect, risk of severe postural hypotension.

Combinations to consider:
With hypotensive drugs: increased hypotensive effect and risk of postural hypotension (additive effect). With CYP3A4 isoenzyme inhibitors (ketoconazole, itraconazole, ritonavir): increase of alfuzosin concentration in blood.

Special Instructions

In some individuals, particularly patients receiving hypotensive treatment, postural hypotension, with or without symptoms (dizziness, fatigue, sweating), may develop within a few hours after taking alfuzosin, as with other alpha1-adreno-blockers.

In such cases, the patient should lie down until the symptoms have completely disappeared. These phenomena are usually temporary, occurring at the start of treatment and usually do not affect the continuation of therapy. The patient should be warned about the possibility of these events.

Patients with coronary insufficiency should not be prescribed alfuzosin in monotherapy. Treatment of coronary artery disease should be continued. If angina returns or worsens, treatment with alfuzosin should be discontinued. Patients should be warned to swallow the tablets whole. The tablets should not be chewed, crushed, crushed, or ground into a powder.

These actions may lead to inappropriate release and absorption of the active ingredient and therefore to side effects that may develop quickly. Particular risks are associated with initiating treatment when events such as dizziness, visual disturbances, and asthenia may occur.

This should be taken into account when performing potentially hazardous activities requiring special attention and quick reactions (driving a car and other vehicles, working with moving machinery, working as a dispatcher and operator, etc.).

Contraindications

Side effects

The adverse effects listed below are given according to the following frequency gradations:

Very common: (≥10%);
Frequent: (≥1%-<10%);
Not common: (≥0.1%-<1%);
Rare: (0.01%-0.1%);
Very rare: (<0.01%) (including isolated cases).

CNS and mental disorders: frequent – weakness, feeling of general discomfort, headache; infrequent – drowsiness, dizziness, cerebral ischemia in patients with ischemic brain disease.

Cardiovascular system disorders: infrequent – tachycardia, palpitations, syncope, orthostatic hypotension; very rare – angina in patients with CHD, atrial fibrillation.

Respiratory system disorders: infrequent – rhinitis.

The digestive system: frequently – nausea, abdominal pain, dry mouth; infrequently – diarrhea; very rarely – damage to hepatocytes, liver disease with cholestasis.

Skin and allergic reactions: infrequent – rash, itching; very rare – urticaria, angioedema.
Other: frequent – asthenia; infrequent – skin flushing, edema, pain in the chest; very rare – priapism.

Overdose

Symptoms: decrease in blood pressure.

In case of overdose the patient should be hospitalized and lie down.

Symptomatic treatment of hypotension should be carried out (administration of vasoconstrictors and plasma substitutes (to increase the volume of circulating blood).

Dialysis is ineffective because of the high degree of binding of alfuzosin to proteins.

Similarities