Pipolfen

Pipolfen, also known by its international generic name promethazine hydrochloride, is a first-generation antihistamine drug. It belongs to the group of phenothiazines and has pronounced sedative, antihistamine, antiemetic, anti-allergic and mild antipsychotic effects. Promethazine blocks H1-histamine receptors, which leads to a reduction in allergy symptoms. In addition, it has a moderate sedative effect due to its effect on the central nervous system, and may enhance the effects of some narcotic analgesics and sedatives.

It's important to know:

• Promethazine may cause severe sedation, so it is important to avoid driving or operating machinery before it is known how the drug affects your ability to concentrate.
• The use of promethazine in high doses or in combination with other sedatives may increase the risk of side effects.
• The drug has a number of contraindications, including pediatric age under 2 years (especially in the form for intravenous administration due to the risk of severe reactions), and conditions in which central nervous system depression is contraindicated.

Before starting to take Pipolfen should consult a doctor who will select an individual dosage and course of treatment, taking into account all available medical indications and contraindications.

Indications Pipolfen

1. Allergic reactions: Promethazine can be used to relieve various symptoms of allergies such as itching, runny nose, urticaria, allergic dermatitis and allergic conjunctivitis.
2. Nausea and vomiting: The drug is used to treat and prevent nausea and vomiting, including those caused by chemotherapy, postoperative condition, movement (motion sickness), and other causes.
3. Sedation and drowsiness: Promethazine may be prescribed to alleviate insomnia and anxiety, as well as a sedative for various medical procedures.
4. Reduction of aggression and agitation: In some cases, promethazine may be used to reduce aggression, agitation, and anxiety in patients with psychiatric or behavioral disorders.
5. Cold and flu symptoms: In some cases, the drug may help with cold and flu symptoms such as runny nose, cough, and sore throat.
6. Antiemetic Therapy in Children: Promethazine may be used in children for the treatment of nausea and vomiting, but is usually used with caution and under the supervision of a physician.

Release form

1. Tablets: For oral administration. The tablets are convenient for use outside of medical facilities and are intended for the treatment of allergies, sedation and prevention of vomiting, and as a sleep aid.
2. Solution for injection: Promethazine in the form of solution for intramuscular (v/m) and sometimes for intravenous (v/v) administration is used in medical institutions for rapid relief of acute conditions, including severe allergic reactions, nausea and vomiting, as well as for preoperative preparation of patients.
3. Syrup: Intended for oral administration, especially convenient for children and adults who have difficulty swallowing tablets. The syrup can be used to treat allergic conditions and for sedation.
4. Suppositories (rectal suppositories): Used for rectal administration and may be prescribed as an alternative when oral intake or injection is not possible, e.g. In cases of severe nausea and vomiting.

Pharmacodynamics

1. Antihistamine Action: Promethazine blocks peripheral and central histamine H1 receptors, resulting in the reduction of a number of histamine-mediated effects such as itching, rash, intestinal cramping, and smooth muscle contraction.
2. AntiemeticAction: Promethazine has an antiemetic effect by blocking dopamine receptors at the terminal ends of nerve fibers in the brain, which may reduce nausea and vomiting.
3. Sedative and sleeping effect: The drug has a central depressant effect on the central nervous system, which leads to sedation and improvement of sleep quality.
4. Anticholinergic action: Promethazine has anticholinergic properties that can lead to various side effects such as dry mouth and difficulty urinating.
5. Antidopaminergic action: The drug blocks dopamine receptors in the brain, which may lead to a decrease in the antiemetic effect of the drug, but may also lead to a decrease in fear and anxiety.

Pharmacokinetics

1. Absorption: Promethazine is well absorbed through the gastrointestinal tract after oral administration.
2. Distribution: Promethazine has high affinity to blood plasma proteins, especially albumin. It is distributed throughout the tissues of the body, including the central nervous system.
3. Metabolism: Promethazine is metabolized in the liver to form active metabolites, including sulfoxide and desmethylpromethazine. These metabolites may also have pharmacologic activity.
4. Excretion: Promethazine and its metabolites are excreted mainly through the kidneys as conjugated metabolites and also through the intestine.
5. Half-life: The half-life of promethazine may vary, but is usually about 10-12 hours.

Dosing and administration

The method of use and dosage of Pipolfen (promethazine hydrochloride) depend on the form of release of the drug, indications for its use and individual reaction of the patient. The following are general recommendations, but you should always follow the instructions given by your doctor and attached to the drug.

Pills

• For adults: The usual dose is 25 mg before bedtime to improve sleep, 25 mg two or three times daily to treat allergies. In some cases, up to 50-75 mg may be recommended to alleviate stress reactions.
• For children over 6 years of age: Dosage is individualized, usually 12.5-25 mg up to twice daily or before bedtime.

Solution for injection

• For adults: When administered intramuscularly to relieve allergy symptoms or used as a sedative, the usual dose is 25-50 mg. The same dosage may be used to relieve nausea and vomiting.
• For children: Intramuscular administration of promethazine in children should be done with caution, the dosage is selected by a doctor.

Syrup

• The dosage of the syrup is selected by the doctor and is usually a lower dose than for tablets or injections, depending on the patient's age and condition.

Suppositories (rectal suppositories)

• Dosage and frequency of use of suppositories are determined by the doctor depending on the clinical situation.

General Guidelines:

• Alcohol and other centrally acting depressants should be avoided when using promethazine, as this may result in increased sedation.
• Patients, especially elderly and debilitated, should be careful when standing up due to possible orthostatic hypotensive effect of the drug.
• It is important to start the drug at a low dose to assess tolerability and avoid heavy sedation, especially in children and elderly patients.

Use Pipolfen during pregnancy

The use of Pipolfen during pregnancy may be limited.

In most countries, Promethazine is listed as Category C by the FDA (U.S. Food and Drug Administration), which means that animal studies have shown adverse effects on the fetus, but there are no sufficient and well-controlled studies in pregnant women.

Therefore, it is recommended to avoid the use of promethazine during pregnancy, especially during the first trimester, when the baby's organs and systems are forming. In some cases, when the benefits of use outweigh the potential risks, a doctor may prescribe promethazine in a short-term regimen or in low doses. However, this should be done under strict medical supervision.

Contraindications

1. Allergic reaction: People with known hypersensitivity or allergic reaction to promethazine or other components of the drug should avoid its use.
2. Respiratory suppression: Promethazine may increase central nervous system depression and cause respiratory suppression, especially in young children. Therefore, it should be used with caution in patients with asthma, obstructive pulmonary disease, or other conditions that may result in decreased respiratory function.
3. Glaucoma: Promethazine may increase intraocular pressure, which can be dangerous for people with glaucoma or a predisposition to developing glaucoma.
4. Bronchial asthma: Promethazine may increase bronchial spasms and worsen the course of bronchial asthma.
5. Liver and kidney diseases: The drug should be used with caution in patients with liver or kidney diseases, as it may increase their negative effects on these organs.
6. Pregnancy and lactation: There is insufficient data on the safety of promethazine use during pregnancy and lactation, so it should be used with caution in these conditions.
7. Pediatric: Promethazine is not recommended for use in children younger than 2 years of age due to the risk of serious side effects such as respiratory depression.

Side effects Pipolfen

1. Drowsiness and decreased concentration: This is one of the most common side effects of promethazine. Patients may feel drowsy, fatigued, and have difficulty concentrating.
2. Dry mouth: Promethazine may cause a decrease in saliva secretion, resulting in a dry mouth sensation.
3. Constipation: Some people may experience constipation while taking Pipolfen.
4. Urinary Retention: Promethazine may cause urinaryretention, especially in people with an enlarged prostate or other medical conditions involving the bladder.
5. Decrease inblood pressure: In some patients, the drug may cause a decrease in blood pressure.
6. Tachycardia or bradycardia: Some people may experience a fast or slow heartbeat after taking promethazine.
7. Increased sensitivityto light: Some patients may experience increased sensitivity to sunlight or other light sources.
8. Muscle cramps or tremors: Promethazine may cause muscle cramps or tremors in some people.

Overdose

1. Sedation and drowsiness: Overdose with promethazine may cause severe sedation and deep sleep.
2. Respiratory depression: An increased dose of promethazine may lead to respiratory depression and in extreme cases even respiratory arrest.
3. Hypotension: Overdose may cause a sharp drop in blood pressure, leading to hypotension and even collapse.
4. Anticholinergic effects: Anticholinergic side effects such as dilated pupils, dry mouth, constipation and difficulty urinating may occur.
5. Tachycardia and arrhythmias: Overdose may cause palpitations and cardiac arrhythmias.
6. Seizure syndrome: In rare cases, seizure syndrome may occur.

Interactions with other drugs

1. Centrally acting drugs: Promethazine increases the depressant effect on the central nervous system of other centrally acting drugs such as sleeping pills, sedatives, analgesics and some antidepressants. This may result in increased sedation and slower reaction times.
2. Alcohol: Consumption of alcohol while taking promethazine may increase its sedative effect and increase the risk of undesirable side effects such as drowsiness and dizziness.
3. Anticholinergic drugs: Promethazine may enhance the anticholinergic effects of other drugs such as antihistamines, antidepressants, antiparkinsonian drugs, which may lead to an increased risk of unwanted side effects such as dry mouth, constipation, difficulty urinating, and tachycardia.
4. Antiparkinsonian drugs: Promethazine may reduce the effectiveness of antiparkinsonian drugs such as levodopa, carbidopa, and other agents used to treat Parkinson's disease.
5. Anticoagulants: Promethazine may increase the anticoagulant effect of drugs such as warfarin, which may increase the risk of bleeding.
6. Antiarrhythmic drugs: Promethazine may increase the QT interval on ECG and increase the risk of arrhythmias when taken concomitantly with antiarrhythmic drugs such as amidarone or sotalol.

Storage conditions

1. Temperature: Promethazine hydrochloride should normally be stored at a controlled temperature of 15°C to 30°C (59°F to 86°F). Avoid extreme temperatures and store the drug in a cool place protected from direct sunlight.
2. Humidity: It is important to avoid exposure of the drug to moisture, so it is recommended to store Pipolfen in a dry place to prevent deterioration or decomposition.
3. Packaging: Make sure that the packaging of Pipolfen is tightly closed after each use to prevent the ingress of moisture or air, which may adversely affect the quality of the drug.
4. Children and pets: Keep promethazine hydrochloride out of the reach of children and pets to prevent accidental use.
5. Shelf life: Observe the shelf life of the drug indicated on the package. Do not use the drug after the expiration date, as its effectiveness may be reduced.