Hydroxyzine Hydrochloride Bristol Laboratories (Hydroxyzine Hydrochloride)

Hydroxyzine Hydrochloride is a first‑generation antihistamine that acts on peripheral H1 receptors to alleviate several conditions.

• Anxiety: reduces symptoms of acute anxiety and tension.
• Pruritus (itching): alleviates itching associated with allergic skin conditions.
• Allergic skin reactions: helps control hives and other histamine‑mediated dermal responses.
• Sedation before or after surgical procedures: provides calming and sedative effects for pre‑operative or post‑operative comfort.

• Hydroxyzine Hydrochloride selectively blocks peripheral histamine H1 receptors, preventing histamine‑induced vasodilation, increased vascular permeability, and sensory nerve activation. Its additional anticholinergic activity contributes to sedation and reduced secretions, while central nervous system penetration adds anxiolytic and anti‑emetic properties. The combined actions result in relief of allergic symptoms, itching, and anxiety.

Hydroxyzine Hydrochloride may cause a range of adverse reactions, from mild to serious.

Common Side Effects

• Drowsiness: feeling unusually sleepy or fatigued.
• Dry mouth: reduced salivation leading to a parched sensation.
• Blurred vision: temporary visual disturbances.
• Constipation: slowed gastrointestinal motility.
• Headache: mild to moderate head pain.
• Dizziness: sensation of light‑headedness or unsteadiness.

Serious or Rare Side Effects

• Cardiac arrhythmia: irregular heart rhythm requiring medical attention.
• Severe hypotension: marked drop in blood pressure causing faintness.
• Seizures: convulsive episodes in susceptible individuals.
• Anaphylaxis: life‑threatening allergic reaction.
• Hepatic injury: signs of liver dysfunction.
• Blood dyscrasias: abnormal blood cell counts or clotting disorders.

When prescribing Hydroxyzine Hydrochloride, clinicians should consider several safety measures.

• Pregnancy: safety not established; avoid unless benefits outweigh risks.
• Elderly: increased sensitivity to sedative and anticholinergic effects.
• Driving: may impair ability to operate machinery; advise caution.
• Drug interactions: review concomitant medications for additive CNS depression.
• Renal/hepatic impairment: dose adjustment may be required based on organ function.
• Store at room temperature: keep in the original container, protect from moisture and light.

Hydroxyzine Hydrochloride can interact with other medicines, requiring attention to the level of risk.

Major Interactions (Avoid)

• CNS depressants: additive sedation and respiratory depression.
• MAO inhibitors: risk of severe hypotension and serotonin syndrome.
• Anticholinergic drugs: increased anticholinergic burden leading to confusion.

Moderate Interactions (Monitor Closely)

• Alcohol: enhances drowsiness and impairment.
• Antihypertensives: may augment hypotensive effect.
• Other antihistamines: increased sedation and anticholinergic side effects.