Hydroxyzine Pamoate

Common Uses

Hydroxyzine pamoate is primarily prescribed for the following conditions:

• Anxiety and Tension: It is used for the short-term relief of anxiety and tension. This includes anxiety associated with emotional disorders or as a supplement for medical conditions where anxiety is a factor.
• Allergic Skin Reactions: It helps manage itching (pruritus) caused by allergic conditions, such as chronic hives (urticaria) and various types of dermatitis, including contact or atopic dermatitis.
• Sedation: It is used as a sedative to help patients feel calm or sleepy before or after surgery and other medical procedures. It is often used in combination with other medications during anesthesia.

Antihistamine Action

Hydroxyzine pamoate belongs to a class of medications known as antihistamines. It works by blocking the action of histamine, a natural substance in the body that causes allergic symptoms. By competing with histamine for specific receptor sites, the medication helps relieve itching, hives, and other skin reactions.

Central Nervous System Effects

In addition to its effects on allergies, hydroxyzine acts on the central nervous system. It is thought to suppress activity in certain subcortical regions of the brain, which helps to:

• Reduce feelings of anxiety and emotional tension.
• Provide a sedative effect to help patients feel relaxed or sleepy before or after surgery.
• Control nausea and vomiting by affecting the signals in the brain that trigger these responses.

While the exact mechanism for its calming effects is not fully established, it is known to provide relief without acting as a general depressant of the brain's outer layer (the cortex).

Common Side Effects

The most frequent side effects of hydroxyzine pamoate are usually mild and may include:

• Drowsiness or sleepiness
• Dry mouth
• Dizziness
• Headache
• Constipation
• Confusion, particularly in older adults

Serious Side Effects

Seek medical attention immediately if you experience serious symptoms, such as:

• Seizures
• Uncontrolled shaking or tremors
• Fast, pounding, or irregular heartbeat
• Severe skin reactions, including redness, rash, or blisters
• Signs of a serious allergic reaction, such as hives, difficulty breathing, or swelling of the face, tongue, or throat

Heart Rhythm Changes

Hydroxyzine has been linked to a heart rhythm problem known as QT prolongation, which can lead to serious or life-threatening heart disturbances. This risk is higher for individuals with certain pre-existing heart conditions, low levels of potassium or magnesium in the blood, or those taking other medications that also affect heart rhythm.

Central Nervous System Depression

This medication causes drowsiness and can significantly impair physical and mental abilities. Activities requiring alertness, such as driving or operating machinery, may be dangerous while using this drug. The sedative effects are increased when combined with alcohol or other medications that cause sleepiness, such as opioids or sleep aids.

Serious Skin Reactions

Rare but serious skin reactions, including acute generalized exanthematous pustulosis (AGEP), have been reported. Symptoms may include a sudden rash, fever, and many small, fluid-filled blisters. If these symptoms appear, the medication is usually stopped immediately.

Pregnancy and Nursing

• Pregnancy: Use of hydroxyzine is contraindicated during the first trimester of pregnancy.
• Nursing: It is not known if hydroxyzine passes into breast milk. Caution is recommended for individuals who are breastfeeding.

Contraindications and Other Risks

• Allergies: Hydroxyzine should not be used by anyone with a history of hypersensitivity to hydroxyzine, cetirizine, or levocetirizine.
• Elderly: Older adults may experience increased sensitivity to the drug, leading to confusion, dry mouth, or an increased risk of falls.

Pregnancy

Hydroxyzine pamoate should not be used during the early stages of pregnancy. While there are no adequate and well-controlled studies in pregnant humans, animal studies have shown that the drug can cause fetal abnormalities when administered at doses significantly higher than the human therapeutic range. If you are pregnant or planning to become pregnant, it is important to discuss the potential risks with your healthcare provider.

Breastfeeding

It is not currently known if hydroxyzine pamoate passes into human breast milk. Because many medications are excreted in breast milk and could potentially cause adverse effects in a nursing infant, healthcare providers generally advise that hydroxyzine should not be used by those who are breastfeeding. You should consult with a clinician to weigh the benefits of the medication against the potential risks to the infant.

Available Forms

Hydroxyzine pamoate is primarily administered by mouth. The available forms include:

• Oral Capsules
• Oral Suspension

The oral suspension is a liquid form of the medication. Other formulations of hydroxyzine, such as tablets or solutions for injection, typically contain the hydrochloride salt rather than the pamoate salt.

FDA Approval and Indications

Hydroxyzine pamoate is approved by the U.S. Food and Drug Administration (FDA) for several specific uses. It is indicated for the symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states where anxiety is manifested. It is also approved for the management of pruritus (itching) due to allergic conditions, such as chronic urticaria and atopic or contact dermatoses. Additionally, it is used as a sedative for premedication and following general anesthesia.

Safety Communications

In 2016, the FDA identified a potential signal of serious risk regarding QT interval prolongation and Torsade de Pointes (serious heart rhythm issues) associated with hydroxyzine. Following this review, the FDA determined that new safety information should be included in the drug labeling to warn healthcare providers and patients about these risks, particularly for individuals with pre-existing heart conditions or those taking other medications that prolong the QT interval.

Regulatory Status and Restrictions

Hydroxyzine pamoate is available by prescription only. It is contraindicated for use during early pregnancy. There are currently no Risk Evaluation and Mitigation Strategies (REMS) or boxed warnings required by the FDA for this medication.

Withdrawal and Dependence

Hydroxyzine pamoate is an antihistamine and is not classified as a controlled substance. Unlike some other medications used to treat anxiety, such as benzodiazepines, hydroxyzine does not typically lead to physical dependence or addiction. Because of this, most people can stop taking the medication without experiencing physical withdrawal symptoms.

Return of Symptoms

While there is no formal withdrawal process, stopping hydroxyzine may cause the symptoms for which it was prescribed to return. This may include:

• Increased feelings of anxiety or tension.
• Return of itching or skin reactions.
• Difficulty sleeping, if the medication was used for its sedative effects.

It is important to follow the instructions provided by a healthcare professional regarding the duration of treatment. If you have concerns about stopping the medication, discuss the best approach for discontinuation with your doctor.