Papaverine hydrochloride

Papaverine hydrochloride is a drug used for problems with the work of the digestive tract. Included in the category of papaverine and its derivatives.

[1], [2], [3], [4], [5], [6]

Indications of the papaverine hydrochloride

It is used in the following situations:

• elimination and prevention of smooth muscle spasms in the field of internal organs against the background of the spastic form of colitis, and in addition pylorospasm or cholecystitis;
• elimination of colic in the kidneys, as well as stomach;
• treatment of impotence, which has a vascular origin;
• therapy with obliterating form of endarteritis and spasms in the region of cerebrospinal vessels, as well as limbs (an integral element of combined treatment).

[7], [8],

Release form

The release is made in the form of a 2% solution for injection, in ampoules of 2 ml. Inside the blister plate there are 10 such ampoules. The box contains 1 or 2 blisters with ampoules.

[9], [10]

Pharmacodynamics

The drug has antispasmodic and antihypertensive properties.

The effect of papaverine is due to its blocking effect on the activity of the PDE4 component. Due to blockade of the enzyme hydrolysis of the cAMP element stops, and its values inside the cells of the vessels of smooth muscles and internal organs increase. The cAMP element reduces the amount of calcium ions entering the cells, and in addition it inactivates the kinase located in the light myosin chains (this is a contractile protein that promotes the processes of muscle contractions).

The medicine helps to relax the smooth muscles of the vessels and internal organs, and at the same time to reduce their tone (respiratory and urogenital system, as well as the gastrointestinal tract). The active substance basically dilates the blood vessels of the arteries and increases the volume of blood flow (this also includes the cerebral blood flow).

[11], [12], [13]

Pharmacokinetics

With the / m and / or the introduction of the drug completely and quickly absorbed. Drugally effective values of drugs within the plasma are 0.2-2 μg / ml. After repeated administration of the drug, its pharmacokinetic parameters remain the same.

Protein synthesis inside the plasma reaches 90%. The drug easily penetrates the gistogematicheskie barriers. Forms a depot inside fatty tissues, as well as the liver (inside it papaverine is biotransformed). The elimination half-life is 0.5-2 hours.

Excretion occurs with urine, in the form of decay products. A small part of drugs (less than 0.5%) is displayed unchanged.

[14], [15], [16], [17]

Dosing and administration

The solution is administered by several methods - in / m, n / k or IV injection.

For adults, a dosage of 20-40 mg is required (equal to 1-2 ml of a 2% solution), which is administered 2-4 times / day (the interval between injections is at least 4 hours). If you need an IV injection of 10 mg of the drug (1 ml), the solution must first be diluted with sodium chloride (10-20 ml of 0.9% solution). For 1 injection, no more than 0.2 g of solution (10 ml) is allowed to enter, and a maximum of 0.3 g (15 ml) per day as a whole.

To eliminate impotence of vascular origin, it is required to inject intracavernosally - in the amount of 10 mg (0.5 ml). The procedure should be followed 20-30 minutes before the alleged sexual contact.

People at the age of 70 years can enter a maximum of 10 mg of the drug at a time (0.5 ml).

Children 1-12 years of age, the solution is administered in the amount of 0.3-0.5 mg / kg 2-3 times / day.

[26], [27],

Use of the papaverine hydrochloride during pregnancy

The solution is sometimes used in late pregnancy, shortly before birth - to reduce uterine hypertension and reduce the risk of premature birth.

Contraindications

Among the contraindications:

• infants up to 12 months;
• state of coma or suppression of respiratory activity;
• glaucoma;
• AV blockade;
• the presence of intolerance against papaverine;
• people over the age of 75 (too high risk of hyperthermia);
• Peyronie's disease (performing intracavernous injections).

[18], [19], [20], [21]

Side effects of the papaverine hydrochloride

The use of the solution sometimes causes the appearance of such side effects:

• constipation or nausea;
• hyperhidrosis or a feeling of drowsiness;
• the development of eosinophilia and an increase in the values of transaminases;
• AV blockade, pressure reduction, ventricular extrasystole;
• Peyronie's disease or priapism caused by intracavernous injection.

[22], [23], [24], [25]

Overdose

Signs of poisoning occur after injection of the solution in a large dose, especially if the patient has kidney or liver disease. Usually, diplopia develops, a feeling of drowsiness or weakness, and pressure decreases.

The drug has no special antidote. To eliminate the violation, you should stop using drugs, perform gastric lavage, give the affected person activated charcoal and milk, and at the same time perform procedures for symptomatic and supportive treatment. This will help increase blood pressure and remove other disorders.

To get rid of priapism, which develops as a result of intracavernous injection of the solution, it is required to inject phenylephrine and adrenaline intracavernously. In severe forms of the disease, hemoaspiration is performed, as well as shunting in the area of the vessels of the penis.

[28], [29], [30], [31], [32],

Interactions with other drugs

As a result of the combination with papaverine, the antihypertensive properties of methyldopa decrease and the effect of alcohol is increased.

For smokers there is an accelerated metabolism of papaverine, therefore its plasma values, as well as medicinal properties, are weakened.

Fentolamine enhances the effectiveness of drug exposure to cavernous bodies of the penis in the case of combined use.

Metamizole with diphenhydramine and diclofenac enhances the spasmolytic effect of papaverine.

Solutions of papaverine hydrochloride do not have drug compatibility with glucose solution (due to partial inactivation of papaverine).

[33], [34]

Storage conditions

Papaverine hydrochloride is required to be kept out of the reach of children, as well as the sunlight spot. Temperature indicators - a maximum of 25 ° C.

[35], [36], [37], [38], [39]

Shelf life

Papaverine hydrochloride is allowed to be used for 2 years after the release of the therapeutic agent.

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