Atarax

Atarax (hydroxyzine) is a medicine belonging to the class of anxiolytics (anti-anxiety agents) and first-generation antihistamines. It is widely used to treat anxiety and tension, as well as a sedative and to reduce itching in allergic reactions. Hydroxyzine is also used for sedation before medical procedures.

Pharmacological properties

1. Anxiolytic action:

   • Hydroxyzine reduces activity in certain areas of the central nervous system, resulting in a reduction in anxiety and tension without significantly depressing the respiratory system, which is often a side effect of stronger tranquilizers such as benzodiazepines.

2. Sedation:

   • It helps to reduce arousal and make it easier to fall asleep, making it useful in treating anxiety-related sleep disorders.

3. Antihistamine action:

   • Hydroxyzine blocks histamine receptors in the body, which helps reduce allergic reactions such as skin itching, rashes, and hives.

Indications Ataraxa

1. Allergic reactions: The drug may be used to relieve symptoms of allergic reactions such as itching, hives, allergic runny nose and skin rashes.
2. Stress and Anxiety: Hydroxyzine may be used as an anxiolytic to relieve anxiety, tension and nervousness.
3. Insomnia: Because of its sedative action, Atarax may be used to improve sleep in patients with insomnia.
4. Other conditions: In some cases, Atarax may be prescribed as an antiemetic (against vomiting) or to reduce seizure activity in epilepsy. It may also be used as premedication before surgeries or procedures.
5. Dermatologic diseases: Hydroxyzine may be used to treat itching and skin irritation, such as eczema or contact dermatitis.

Release form

1. Pills:

   • Atarax is most commonly available as oral tablets.
   • Tablets may contain 10 mg, 25 mg, or 50 mg of hydroxyzine, depending on the dosage.

2. Capsules:

   • In some countries, Atarax may be available as capsules, which are also intended for oral administration.

3. Syrup:

   • For children and adults who have difficulty swallowing tablets, Atarax may be available in syrup form, making the medication easier to take.

4. Solution for injection:

   • In some cases, an intramuscular solution may be available for use in hospitalized patients for rapid sedation.

Pharmacodynamics

1. Antihistamine action:

   • Hydroxyzine is an antihistamine drug that blocks peripheral and central H1-histamine receptors.
   • This has the effect of reducing the release of histamine and suppressing its action, which reduces the symptoms of allergic reactions such as itching, redness, runny nose and swelling.

2. Anxiolytic action:

   • Hydroxyzine has anxiolytic effects, that is, the ability to reduce anxiety and tension.
   • This is due to its ability to block central H1 receptors, as well as its effects on serotonin and adrenergic systems.

3. Sedation:

   • Hydroxyzine has sedative properties that help reduce central nervous system excitation.
   • This makes it useful for relieving insomnia and helps improve the quality of sleep.

4. Musculospasmolytic action:

   • Hydroxyzine also has the ability to reduce muscle tension and spasms due to its effect on the central nervous system.

5. Antiemetic action:

   • In some cases, hydroxyzine may be used to relieve nausea and vomiting, especially when combined with antihistamine properties.

6. Anti-emetic action:

   • Hydroxyzine may also be used as an antiemetic to relieve nausea and vomiting, especially in cases involving histamine or other factors that cause nausea.

Pharmacokinetics

1. Absorption: Hydroxyzine is usually rapidly absorbed from the gastrointestinal tract after oral administration. Maximum blood concentrations are usually reached 1-2 hours after ingestion.
2. Distribution: It is well distributed in organs and tissues of the body, including brain tissues. Hydroxyzine has high affinity to blood plasma proteins (approximately 90%).
3. Metabolism: Hydroxyzine is metabolized in the liver with formation of active metabolite cetirozine with participation of cytochrome P450 enzymes. Cetirozine has antihistamine properties and is able to penetrate the blood-brain barrier.
4. Excretion: Hydroxyzine metabolites are excreted mainly with urine as conjugates and free forms.
5. Half-life: The half-life of hydroxyzine is about 20 hours, which may result in the need to take the drug multiple times during the day to maintain constant levels in the blood.

Dosing and administration

Method of application

• Oral administration: Atarax tablets or capsules are taken orally, regardless of food intake, but with enough water to facilitate swallowing.
• Syrup: Used for ease of dosing, especially in children or adults with swallowing difficulties.

Dosage

For adults

• Anxiety: The usual starting dose is 25 mg taken 3-4 times daily. The dose can be adapted according to clinical response and tolerability up to a maximum dose of 100 mg daily.
• Sedation before medical procedures: Usually prescribed 50-100 mg 30 minutes before the procedure.

For children

• Anxiety and sedation: The dosage for children is based on body weight - approximately 1 mg/kg body weight per day. This dose is usually divided into several doses (e.g. 12.5 mg three times a day).
• Itching and allergic reactions: Also 1 mg/kg body weight per day, divided into several doses.

Special Instructions

• Hydroxyzine may increase the effect of alcohol and other central nervous system depressants. Alcohol consumption should be avoided during treatment.
• Driving vehicles or operating machinery during treatment with hydroxyzine is not recommended, as it may cause drowsiness or dizziness.
• Caution should be exercised when using hydroxyzine in patients with impaired renal or hepatic function and in elderly patients due to the risk of side effects.

Use Ataraxa during pregnancy

When used during pregnancy, extra caution should be exercised as its safety for pregnant women and the developing fetus has not been fully established.

Effect on pregnancy

1. Teratogenic effects:

   • Hydroxyzine penetrates the placenta. Animal studies have shown possible teratogenic effects, but controlled studies in pregnant women have not been conducted. For this reason, the use of hydroxyzine during pregnancy, especially in the first trimester and before delivery, is not recommended.

2. Effects on the fetus and newborns:

   • Taking hydroxyzine during the last weeks of pregnancy may cause central nervous system depression in the newborn. There is also information about possible development of withdrawal syndrome in newborns if the mother took hydroxyzine at the end of pregnancy.

Recommendations

• The use of hydroxyzine during pregnancy is acceptable only when the potential benefit to the mother exceeds the potential risk to the fetus. A doctor should always be consulted before starting this medicine.
• During pregnancy, women should avoid using medications unless absolutely necessary and on the advice of a doctor, considering the possible risks and benefits.

Alternatives

• If anxiety or allergies need to be treated during pregnancy, other safer alternatives may be considered. There are antihistamines and anti-anxiety medications that are considered safer during pregnancy. Always consult your doctor for the most appropriate and safe treatment option.

Contraindications

1. Allergy to hydroxyzine or other components of the drug: Patients with known hypersensitivity to hydroxyzine should avoid its use.
2. Early Pregnancy and Lactation: Hydroxyzine is not recommended for use during pregnancy and lactation because its safety to the fetus or child has not been established.
3. Porphyria: The drug may provoke exacerbation of this disease.
4. Prolonged QT interval: Hydroxyzine may prolong the QT interval, which is dangerous in patients with an associated predisposition or pre-existing QT prolongation.
5. Severe hepatic impairment: Hydroxyzine is metabolized in the liver and its use may not be safe in severe hepatic impairment.
6. Severe renal impairment: Since hydroxyzine is excreted through the kidneys, dose adjustment may be necessary in severe renal impairment.
7. Glaucoma: Hydroxyzine may increase intraocular pressure, making its use risky for patients with glaucoma.
8. Urinary Retention: Because hydroxyzine may exacerbate this problem, it should be used with caution in patients with urinary tract disease.

Side effects Ataraxa

Common side effects

• Drowsiness: This is one of the most common side effects, as hydroxyzine can act sedatively.
• Dizziness: May occur against the background of general depressing effect on the central nervous system.
• Fatigue: Feeling tired or lethargic is also a common consequence of taking hydroxyzine.

Digestive system

• Dry mouth: Hydroxyzine may decrease saliva production, resulting in a feeling of dryness.
• Nausea: Nausea may occur in some cases, although this is a less common side effect.
• Constipation: Hydroxyzine may affect the digestive system, causing constipation.

Nervous system

• Headache: Sometimesheadaches may occur as a side effect.
• Tremor or increased agitation: These symptoms are less common but may occur in some patients.

Cardiovascular system

• Tachycardia: A fast heartbeat may occur as a reaction to a medicine.

Allergic reactions

• Urticaria: Rashes on the skin that may be accompanied by itching.
• Quincke's edema: A life-threatening condition characterized by swelling of tissues, including the larynx.

Other rare side effects

• Dyskinesia: Involuntary movements, especially facial tics or gesticulations.
• Photosensitization: Increased sensitivity to sunlight.

Serious side effects

Although they are rare, some side effects can be serious and require immediate medical attention:

• Respiratory depression: Especially in patients with pre-existing respiratory disease.
• Seizures: In particularly rare cases may cause convulsive reactions.

Overdose

1. Central nervous system (CNS) depression:

   • One of the main effects of hydroxyzine overdose is sedation and central nervous system depression.
   • This can manifest as deep sleepiness, decreased responsiveness to external stimuli, drowsiness, slowed breathing, and even coma.

2. Cardiovascular disorders:

   • An overdose of hydroxyzine can cause arterial hypotension (low blood pressure), which can lead to dizziness, weakness, fainting, and even collapse.
   • It is also possible to develop cardiac arrhythmias, including decreased heart rate (bradycardia) or increased QT interval, which can lead to serious heart rhythm disturbances.

3. Other unwanted effects:

   • Other possible effects of hydroxyzine overdose include dilated pupils (mydriasis), dry mouth, constipation, urinary retention, agitation, restlessness, and seizures.

Interactions with other drugs

1. Centrally acting depressants: Atarax may increase thedepressant effects of other centrally acting drugs such as sedatives, alcohol, sleeping pills, antidepressants and narcotics. This may result in increased sedation and muscle relaxation.
2. Anticholinergic drugs: Atarax may increase the anticholinergic effects of other drugs such as antihistamines, antipsychotics, antidepressants, antiparkinsonian drugs and antitremor drugs. This may lead to impairment of bowel function, urination, vision and cognitive function.
3. M-cholinoblockers: Atarax may increase the effect of m-cholinoblockers such as anticholinergic drugs, antipsychotics, antidepressants and antiparkinsonian agents. This may increase the risk of side effects associated with m-cholinergic receptor blocking.
4. Central stimulants: Atarax may reduce the effectiveness of central stimulants such as amphetamine and dexamphetamine due to its sedative action.
5. Cytochrome P450 3A4 (CYP3A4) inhibitors: CYP3A4 inhibitors, such as ketoconazole and ritonavir, may increase the blood concentration of atarax and potentiate its effects.