Doctors prescribe REZIRA to treat cough and stuffy nose associated with the common cold, flu or hay fever.
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Other, off label uses for this medicine

In addition to being an antitussive, ingredients in REZIRA also relieve pain and cause sedation. Other ingredients relieve sinus pressure and congestion.

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Hawthorn Pharmaceuticals, Inc., offers REZIRA in an oral solution in 16-oz bottles.

Each 5 ml dose of REZIRA contains 5 mg of hydrocodone bitartrate and 60 mg of pseudoephedrine hydrochloride.

The recommended dose for adults 18 years and older is 5 ml of REZIRA every four to six hours as needed, not to exceed four doses (20 ml) in a 24-hour period.

Consumers should use an accurate measuring device rather than a household spoon to measure a dose of REZIRA. Using an inaccurate measuring device may result in inadequate dosing or overdose.

Children under the age of 18 years should not use REZIRA. Hydrocodone may cause dangerous or fatal breathing problems in children under the age of six years.

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The hydrocodone in REZIRA depresses the cough reflex in the brain’s breathing center, the medulla.

Hydrocodone is a semi-synthetic opioid pain reliever, sometimes called a narcotic. Hydrocodone acts with the central nervous system, or CNS, to relieve pain, cause sedation and create a pleasant sense of euphoria. Hydrocodone stiffens smooth muscles, like those in the digestive tract and skin, to make these muscles less functional.

Pseudoephedrine eases nasal congestion by shrinking blood vessels lining the nose, making it easier to breathe.

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Respiratory Depression

Hydrocodone acts on respiratory centers in the brain; this action may result in respiratory depression, a potentially fatal breathing problem. During respiratory depression, the lungs do not adequately exchange oxygen for carbon dioxide and other blood gases. Symptoms of respiratory depression include slow or shallow breathing, irregular breathing patterns and a blue color around the victim’s eyes, mouth and fingertips. Effects are dose-dependent, meaning higher doses of REZIRA may cause more profound respiratory depression.

Hydrocodone overdose may cause fatal respiratory depression in adults; any amount of hydrocodone can cause fatal respiratory depression in children younger than six years.

Physicians use naloxone to counteract the effects of respiratory depression, especially in cases of overdose.

Head Injury and Increased Intracranial Pressure

Along with causing respiratory depression, hydrocodone may increase fluid pressure surrounding the brain and spinal cord. These effects may be markedly exaggerated in the presence of a head injury, tumor or pre-existing increases in pressure inside the skull. Additionally, the hydrocodone in REZIRA may obscure the healing process in patients with head injuries.

Acute Abdominal Conditions

The hydrocodone in REZIRA may obscure the diagnosis or healing process in patients with acute abdominal conditions.

Drug Dependence

Using REZIRA continuously for more than a few weeks may result in physical dependence, increased tolerance or addiction. Quitting REZIRA abruptly may cause unpleasant withdrawal symptoms in opioid-dependent person.

Cardiovascular and Central Nervous System Effects

The pseudoephedrine in REZIRA may affect the cardiovascular system and CNS in some patients, causing insomnia, dizziness, weakness, shakiness or irregular heartbeat in some consumers. This medication may cause seizures or cardiovascular collapse with very low blood pressure.

Liver and Kidney Dysfunction

Patients with severe liver or kidney dysfunction should use REZIRA with care. The liver clears hydrocodone from the body while the kidneys remove excess pseudoephedrine; dysfunction in these organs may cause an unsafe rise in hydrocodone or pseudoephedrine levels.

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REZIRA may cause dizziness, drowsiness or mental clouding. Alcohol and other CNS depressants may enhance these effects. Consumers should not drive a motor vehicle or operate heavy machinery until determining how REZIRA affects them.

Individuals who are allergic to hydrocodone, pseudoephedrine or any ingredient in REZIRA should not use this product.


Patients with a known hypersensitivity to hydrocodone or pseudoephedrine should not use REZIRA. Those who have taken MAOIs in the previous 14 days should not use this medication. Individuals with very high blood pressure, severe heart disease, urinary retention or some types of glaucoma should not use REZIRA.

Pregnancy, Delivery and Nursing

The FDA classifies drugs according to the potential risk to the mother and baby. The FDA classifies REZIRA as a Pregnancy Category C, meaning there are no well-controlled studies to indicate the negative effects REZIRA has on pregnant woman but that she should not take this drug unless the benefits clearly outweigh the risks.

Babies born to women who receive REZIRA during labor and delivery will suffer some degree of respiratory depression after birth, especially if the mother received high doses.

Babies born to women who regularly take REZIRA shortly before delivery will be born physically dependent on hydrocodone; these babies will experience withdrawal symptoms in the first few days of life. Neonatal withdrawal symptoms include irritability, excessive crying, frequent stools, tremors and hyperactive reflexes. These babies will display excessive sneezing, yawning, rapid breathing and fever.

The hydrocodone and pseudoephedrine in REZIRA passes into breast milk and may be harmful to a nursing baby. Mothers should only use REZIRA during breastfeeding when the benefits to the mother clearly outweigh the risk to the nursing child.

Medical History

REZIRA may worsen some conditions or interfere with treatment; some illnesses may change the way REZIRA works for the consumer. Those with diabetes, thyroid disease, Addison's disease, prostatic hypertrophy or urethral stricture and asthma should use REZIRA with caution.

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Drug Interactions

Scientists have not yet performed studies to determine how REZIRA interacts with other drugs but hydrocodone and pseudoephedrine may interact with other medications in unsafe or unfavorable ways.

Using REZIRA with other opioids, antihistamines, antipsychotics, ant-anxiety drugs or other CNS depressants, including alcohol, may enhance CNS depression.

Using some types of antidepressants, such as MAOIs or tricyclic antidepressants, along with REZIRA may increase the effect of either the antidepressant or the hydrocodone in REZIRA. Additionally, using REZIRA within two weeks of an MAOI may cause a dangerous increase in blood pressure.

The hydrocodone in REZIRA may interact with anticholinergic drugs, used to reduce stimulation of smooth muscle groups, like those in the digestive tract. Using REZIRA with anticholinergic drugs may cause the serious type of bowel obstruction, paralytic ileus.

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Side effects

The hydrocodone in REZIRA may cause respiratory depression, drug dependence, increased intracranial pressure, decreased mental alertness and impaired physical and cognitive abilities, or paralytic ileus. Pseudoephedrine may cause CNS side effects including insomnia, dizziness, weakness, tremor or seizures. Cardiovascular side effects include irregular heartbeat, high blood pressure and collapse of the cardiovascular system.

Because REZIRA acts on the CNS and cardiovascular systems, respiratory centers and smooth muscle groups of the digestive tract and skin, REZIRA may cause adverse reactions affecting these areas. The most common side effects associated with REZIRA affect the nervous and cardiovascular systems, but also affect the skin, digestion or the urinary system.

Nervous system side effects include sedation, dizziness drowsiness, mental clouding, impaired mental performance and lethargy. Other CNS side effects include anxiety, fear, nervousness, sleeplessness, irregular heartbeat, mood changes and the emotional opposite of euphoria, dysphoria.

REZIRA may affect the cardiovascular system to cause fast or slow heartbeat, palpitations, syncope, a shock-like state, high blood pressure, low blood pressure or blood pressure than changes when the individual stands up.

Gastrointestinal side effects include constipation, nausea and vomiting. Ambulatory patients may experience nausea and vomiting more frequently than consumers confined to a bed may. Urinary side effects include spasms and urinary retention.

REZIRA may cause dermatological side effects including itching and rash.

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It is possible to overdose on the hydrocodone or the pseudoephedrine components of REZIRA; both types of overdose are serious medical emergencies. Symptoms of hydrocodone overdose include respiratory depression, extreme sleepiness that worsens to stupor or coma, limp muscles and cold, clammy skin. Slow heartbeat and low blood pressure sometimes occur. In cases of severe overdose, the victim may stop breathing, suffer a heart attack and die.

Symptoms of pseudoephedrine include headache, nausea, vomiting, sweating, thirst, fast heartbeat, difficulty urinating, chest pain, palpitations, insomnia, muscle weakness and tenderness. The individual may seem giddy, anxious or restless; some suffer toxic psychosis with delusions and hallucinations while others suffer irregular heartbeat, collapse of the circulatory system, seizures, coma and respiratory failure.
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Hydrocodone causes a pleasant euphoria that makes REZIRA attractive to recreational drug abusers. The DEA ranks drugs according to their relative potential for abuse. The DEA categorizes REZIRA as a class III narcotic, meaning it poses the same relative risk for abuse as anabolic steroids. To reduce the risk for abuse, REZIRA is available only by prescription.

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Abusing REZIRA or using this medication continuously for more than a few weeks increases the risk the consumer will develop physical dependence and experience withdrawal symptoms when he stops using REZIRA. The presence of withdrawal symptoms does not necessarily indicate criminal abuse; it is possible to become opioid-dependent while using REZIRA for therapeutic reasons as directed by a physician.

Withdrawal causes uncomfortable physical symptoms and demoralizing psychological symptoms that can make it difficult to stop using REZIRA. Consumers may be able to avoid flulike withdrawal symptoms by taking successively smaller doses increasingly further apart. Overpowering withdrawal symptoms prevent many people from quitting REZIRA.
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Many institutions now offer detoxification services to help people overcome dependence on REZIRA and other drugs. Detoxification specialists administer drugs to lower hydrocodone levels along with drugs to ease withdrawal symptoms. While inpatient detoxification reduces withdrawal symptoms, it does not shorten the detoxification process.
Rapid detox is the most humane and effective form of detoxification available today. Board-certified anesthesiologists specially trained in rapid detox procedures sedate and anesthetize patients while giving them standard detoxification and anti-withdrawal drugs. The patient dozes in a comfortable “twilight sleep,” then awakens with no recollection of the grueling and demeaning symptoms of withdrawal.

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REZIRA should be stored at temperatures between 68 degrees Fahrenheit and 77 degrees Fahrenheit.

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