Hydroxyzine (Oral)


Hydroxyzine is an oral medication used to treat itching from allergic reactions associated with chronic urticarial and atopic or contact dermatoses along with histamine reactions in some pain medication. For oral medicine, it comes in tablets, capsules, syrup, and suspension. It is also used to control symptoms of psychotic disorders such as anxiety, tension or agitation, and to combat nausea and vomiting. It reduces the central nervous system activity and acts as an antihistamine for allergic reactions such as hives, rash, or itching. It cannot be used with certain pre-existing medical problems and has a long list of medication it interacts with. Consult with a doctor about the risks. Adults and children can take it; however, people over 65 may have some conditions worsen.

Hydroxyzine is useful when paired with opioid medications because it helps the opioids work better so lower dosages can be taken and it relieves the histamine reactions from opioids. It can be used before and after general anesthesia and childbirth. It is even sometimes used for opioid and alcohol withdrawal and to treat insomnia. It is part of a group of sedating antihistamines and while it is not a cortical depressant it has anticholinergic properties which suppress regions of the central nervous system. It alleviates nausea and vomiting by blocking acetylcholine, and it is used as a muscle relaxant as well.

Conditions Treated

  • Itching
  • Nausea
  • Vomiting
  • Sedation
  • Anxiety
  • Tension
  • Insomnia
  • Opioid or alcohol withdraw

Type Of Medication

  • Antihistamine

Side Effects

Hydroxyzine was approved before side effects were required to be reported and all possible side effects are not known. It is important to report any side effects which can be associated with hydroxyzine. Also report any hallucinations, seizures or signs of allergic reaction such as itching, rash, hives, swelling around the face, and breathing problems to your doctor. Most side effects experienced are minor and easy to treat. Serious reactions are less likely; however, report to the doctor any unusual symptoms since starting treatment.

If any of these side effects are experienced, seek medical treatment right away. If overdose symptoms are experienced, also seek medical attention immediately. Vomiting may need to be induced for an overdose, and vitals and ECG must be monitored frequently. Common reported side effects are dizziness, sleepiness, blurred vision, headache, dry mouth, difficulty urinating, and upset stomach; however, any other side effects experienced should be told to your doctor. For a full list of side effects, look at the manufacturer information provided with the medication.

Requires medical attention:

  • Chest pain and discomfort
  • Cough, shortness of breath, or chest tightness
  • Difficulty swallowing
  • Dizziness or fainting
  • Fast heartbeat, irregular or slow heart rate
  • Hives, skin rash, itching, or puffiness around face
  • Unusual tiredness or weakness

Overdose symptoms:

  • Decreased awareness or responsiveness
  • Drowsiness or severe sleepiness
  • Nausea
  • Seizures
  • Vomiting

Some side effects may not require medical attention and can disappear once your body adjusts to medication. The doctor may be able to provide prevention tips to reduce these side effects. Consult a doctor if they get worse or become bothersome.

Do not require medical attention:

  • Shakiness in legs, arms, hands, or feet
  • Dry mouth
  • Headache
  • Constipation and confusion in older patients
  • Hallucinations


Take hydroxyzine as prescribed by a doctor - it will be different for each individual. The prescribed doses are based on the strength of the medication and the condition being treated determines the number of doses, doses per day, and length of time medicine is taken. Take before or after eating and swallow pills whole or shake the liquid well before use. When giving liquid to children, carefully measure the correct dosage labeled on the bottle. It does not increase gastric secretion or acidity. It absorbs quickly and starts working in as little as 15 minutes. Most people do not need an antihistamine for long periods of time and should discontinue use once symptoms stop. If a dose is missed, take it immediately unless it is almost time for next dose. The following is information about average doses; always take it the way a doctor prescribes.

To help control anxiety and tension:

O Adults'50 to 100 milligrams (mg) 4 times a day.

O Children 6 years of age and olde'50 to 100 mg per day, divided in small doses.

O Children younger than 6 years of ag'50 mg per day, divided in small doses.

To relieve the symptoms of an allergic reaction:

O Adults'50 to 100 milligrams (mg) 4 times a day.

O Children 6 years of age and older'50 to 100 mg per day, divided in small doses.

O Children younger than 6 years of age'50 mg per day, divided in small doses.

For controlling anxiety and to produce sleep before surgery:

O Adults'50 to 100 milligrams (mg) a day.

O Children'Dose is based on body weight and must be determined by your doctor. The dose is usually 0.6 milligrams (mg) per kilogram (kg) of body weight per day.


It is recommended to not take hydroxyzine with these medications. This is not a complete list of medications to avoid with hydroxyzine; the list is rather long so tell the doctor about any of these types of medication. It is helpful to create a list of all medications to share with the doctor, and it should include prescription, over-the-counter, vitamins, or any supplements. It is always important to discuss medications to avoid any dangerous interactions.

Combining hydroxyzine with certain medications increases the risk of dangerous side effects. These include acetylcholinesterase inhibitors, anticholinergic, phenothiazine, and any other medication which causes drowsiness. Taking it with acetyl cholinergic inhibitors can cause both medications to be less effective, and combining with anticholinergic medication can increase the risk of side effects. Taking it with phenothiazine may increase the risk of hydroxyzine causing an irregular heartbeat. Both pramlintide and hydroxyzine slow the movement of food in the digestive tract and taking them together increases the risks of constipation and nausea.

  • Amifampridine
  • Amisulpride
  • Bepridil
  • Cisapride
  • Dronedarone
  • Mesoridazine
  • Pimozide
  • Piperaquine
  • Saquinavir
  • Sodium Oxybate
  • Sparfloxacin
  • Terfenadine
  • Thioridazine
  • Ziprasidone

Avoid with these types of medication

  • Alcohol
  • Barbiturates for sleep or seizures
  • Cold or allergy
  • Anxiety
  • Pain
  • Sleep
  • Muscle relaxants
  • Certain antipsychotics
  • Certain antidepressants
  • Certain antibiotics


Hydroxyzine may cause drowsiness, do not drive or operate heavy machinery until affects are known. Avoid drinking alcohol and other central nervous system depressants as it increases their affects. It may cause some people's skin to be more sensitive to sunlight.

Before using hydroxyzine, consult a doctor about any possible risks. Tell them about any unusual or allergic reactions to this medication, and all other allergies including food, animals, dye, and preservatives. While studies show no geriatric-specific problems, elderly people are likely to experience unwanted side effects and worsening of age-related problems. Anyone over 65 should be aware of the risk of worsening problems.

Tell the doctor if you are pregnant or planning to become pregnant and whether breastfeeding currently because the risks are unknown. Without adequate studies to determine the risk to infants, it is not recommended to take Hydroxyzine while breastfeeding. Taking hydroxyzine with certain medicines can have an interaction which could make medicines less effective, increase effects, or increase the risk of irregular heartbeat. Discuss all medicines whether prescription, over-the-counter, vitamins, or supplements, and disclose all medical conditions to your doctor beforehand.

CNS depressants

  • Antihistamines
  • Prescription pain medicine or narcotics
  • Seizure medication or barbiturates
  • Muscle relaxants
  • Anesthetics including some dental

Tell your doctor about any pre-existing medical conditions. It is not recommended for patients with prolonged QT interval or other heart rhythm conditions, or family history of heart rhythm problems. Reported cases of QT prolongation occurred mostly in patients with risk factors for prolonged QT such as heart disease or electrolyte imbalance. These medical conditions in elderly people are more likely to worsen with use of this medicine and people over 65 should take with caution.

Medical problems

Risk factors


Store hydroxyzine in a closed container and keep away from heat, moisture, and direct light. Keep it in the container it comes in and out of the reach of children and pets. Do not keep outdated medication and dispose of properly; however, do not flush in order to avoid accidental exposure. The best way to dispose of outdated or unused medications is through a medicine take back program. Ask a pharmacist or contact your local recycling and garbage department to find out about any programs in the community.

Drug enforcement agencies host medicine take back programs and some local law enforcement host them as well. Contact local waste management to learn about disposal options and guidelines. To dispose in household trash, mix pills with dirt, kitty litter, or used coffee grounds in a plastic bag and throw away. Be sure to scratch all information off the container before disposing in trash. Always keep out of reach of children, do not rely on child resistance lids because 45% of cases where children had accidental exposure opened child resistant lids.


Hydroxyzine is an antihistamine with sedative properties and is used to treat allergic reactions, symptoms of anxiety or tension, nausea and vomiting. It is commonly used to improve the effectiveness of opioid medication and results in lower doses of opioids needed. Side effects are possible; however, not everyone experiences them. Most are minor and either require no treatment or are easily treated. Serious reactions to hydroxyzine are less common in patients. Also consult with doctor about any pre-existing medical problems, medications, allergies, vitamins and supplements because hydroxyzine interacts with many medicines and some medical problems. Discuss risk factors with your doctor to determine if it is safe to take and report any possible side effects. Always take as directed; however, know what the signs of overdose are in case of any accidental exposure to others or accidentally taking too much medicine.

Hydroxyzine is not recommended for women who are pregnant or breastfeeding because the risks are not known. People over 65 may have pre-existing conditions worsen, such as added confusion to Alzheimer's patients. It is not recommended to use in patients with irregular heart rhythm or a family history of heart rhythm problems. It is important to understand all warnings and precautions before taking medicine and read the manufacturer's leaflet which comes with medicine for full lists of warnings, side effects, and other important information related to hydroxyzine. Avoid any central nervous system depressants including alcohol because it increases the effects of the depressant.

Hydroxyzine works as an antihistamine for allergic reactions and histamine reaction produced by opioids. It relieves anxiety, tension, and agitation by activating certain parts of the brain. It causes skeletal muscles to relax and treats nausea and vomiting by blocking acetylcholine. It can also relieve itching associated with atopic or contact dermatoses and chronic urticarial.