Fentanyl Hydrochloride

  • Generic Name or Active Ingridient: Fentanyl
Drug Class: Fentanyl Hydrochloride > Fentanyl > Fully Synthetic Opioid > Opioids > Opioid Agonist > Analgesic.


Doctors prescribe fentanyl hydrochloride, otherwise known as fentanyl HCl, to relieve short term, moderate to severe pain after surgery. This medication is only for use in hospitals and should be discontinued before the patient is discharged. Your doctor may recommend using fentanyl hydrochloride to treat conditions other than post-operative pain.

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Other, off label uses for this medicine

While there are off-label uses for this medication, the FDA reports some physicians prescribe fentanyl hydrochloride inappropriately. These off-label and contraindicated uses include headaches and for occasional or mild pain. Inappropriate use of fentanyl raises the risk for abuse, overdose and death.

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Many hospitals now offer patient-controlled analgesia, or PCA, where a patient administers pain relievers to himself with the touch of a button. Fentanyl hydrochloride is available in an iontophoretic transdermal system, a technique using a small electric charge to deliver a dose of medicine through the skin. The IONSYS is a patient-controlled system that provides on-demand pain relief for up to 24 hours or a maximum of 80 doses, whichever comes first.

After surgery, the nurse or doctor places the IONSYS system on the patient's upper outer arm or chest. When the patient double clicks the button, the system delivers the equivalent of 44.4 mg of fentanyl hydrochloride over a 10-minute period. A patient may request a maximum of six 40-mcg doses per hour, with a maximum daily dose of 3.2 mg of fentanyl hydrochloride. Up to three consecutive IONSYS systems may be used sequentially, each applied to a different section of skin, for a total of 72 hours of pain relief.

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Fentanyl is stored in fat and muscles, and then slowly released into your bloodstream, where it then binds to nerve endings in your brain, spinal cord and other tissue to disrupt pain signals. Fentanyl is lipophilic, which means it literally "likes fat." This lipophilic nature makes Fentanyl extremely effective because it penetrates the central nervous system more readily than less lipophilic compounds. As a result, Fentanyl is about 100 times stronger than morphine. Its primary actions are analgesia and sedation. This medication increases your tolerance to pain and decreases your perception of suffering, although you may still recognize the presence of pain.

In addition to analgesia, fentanyl HCl alters mood, causing euphoria and dysphoria, or feelings of extreme happiness or extreme sadness. It also depresses the respiratory system and cough reflex, making your brain apathetic about the need to cough and breathe. This medication also constricts pupils and may cause drowsiness. Fentanyl hydrochloride may cause nausea and vomiting, more so in ambulatory patients than patients restricted to bed rest. Ambulatory patients are more likely to experience postural syncope, or dizziness when standing, than are recumbent patients.

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Do not use fentanyl HCl if you are allergic to fentanyl or cetylpiridinium chloride, otherwise known as the brand name Cepacol. Symptoms of an allergic reaction include hives, difficulty breathing and swelling of the face, lips and throat.

Fentanyl HCl increases the tone of smooth muscles and, as a result, decreases the propulsive contractions of the gastrointestinal tract, which slows down your digestive system. This may result in constipation associated with opioid use. Opioids such as fentanyl HCl may increase pressure in the biliary tract; patients with biliary colic may experience worsening pain rather than pain relief after taking fentanyl HCl. Talk with your doctor about ways to decrease constipation and improve bowel function while taking fentanyl HCL.

Your physician may change the dosage or recommend a different post-operative pain medication if you have a history or are currently experiencing certain medical conditions. Fentanyl HCl may worsen your condition or interfere with treatment. Your ailment may change the way fentanyl hydrochloride works in your body. Your doctor may increase dosage if you are already tolerant to opioids.

Fentanyl HCl, like other opioids, may be habit forming. Forming a habit may make discontinuing fentanyl HCl more difficult without the assistance of trained rehabilitative professionals. The fear of developing a habit should not deter you from using this medication to relieve your pain.

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Inappropriate usage of fentanyl hydrochloride may result in dangerous overdose or death. Never touch the sticky side of the fentanyl hydrochloride delivery system, known as hydrogel; doing so may cause exposure or overdose to fentanyl. Ingestion or contact with mucus membranes or unintended exposure to the hydrogel containing the active ingredient, fentanyl hydrochloride, could lead to unintentional absorption of a potentially fatal dose of this potent opioid. Call for the nurse if your fentanyl hydrochloride system detaches from your body - do not attempt to put it back on your body yourself. If exposure were to occur, rinse the affected area with water only; soap, alcohol or other solvents may enhance fentanyl hydrochloride's ability to penetrate the skin.

The half-life of fentanyl hydrochloride is a lengthy 11 hours, meaning this drug stays in your system a long time after exposure to the opioid. Medical personnel will monitor your condition for several hours after removing the system from your skin. More Warnings About Using Fentanyl Hydrochloride

Drug Interactions

Taking fentanyl HCL along with other opioids, sedatives, hypnotics, general anesthetics, phenothiazines, tranquilizers, skeletal muscle relaxants, sedating antihistamines or alcoholic beverages may enhance the depressive effects of fentanyl hydrochloride. Give your doctor a complete list of all your medications, including prescription drugs, over-the-counter medications, vitamin supplements and herbal remedies. Do not start, stop or change the way you take any medication while you are using fentanyl hydrochloride.

Rifampin, carbamazepine, phenytoin, and Saint Johns Wort may increase the rate at which fentanyl HCl is cleared from your body, reducing the effectiveness of fentanyl hydrochloride. Medications such as erythromycin and other macrolide antibiotics, azole antifungal agents such as ketoconazole or ritonavir and other protease inhibitors may slow down the rate at which fentanyl HCl leaves your system, which could increase or prolong adverse drug effects associated with fentanyl hydrochloride, such as respiratory depression.

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Side effects

Patients have reported side effects while using fentanyl hydrochloride. Most common side effects are not serious. Tell the nurse if your side effects become intolerable or if they do not go away. Common side effects include nausea, vomiting or stomach pain.

Some side effects can be serious. Notify your doctor or nurse if you experience any serious side effects while taking fentanyl hydrochloride. He may stop fentanyl hydrochloride or change the dosage. Serious side effects include weak or shallow breathing, severe weakness, feeling light-headed or fainting. This medication may also cause you to experience cold, clammy skin or pale skin, easy bruising or bleeding.

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The IONSYS delivery system reduces the risk for overdose because the machine will not allow a patient to take more medication than has been programmed into the system. After surgery, nurses will administer other medications until the patient is awake enough to operate the system in a safe manner. To reduce the risk for overdose, only the patient should activate the dosing system.

Potential for lethal overdose is possible if the patch becomes dislodged from the patient's body, exposing the pharmaceutical substances on the bottom of the patch. If your system falls off your skin, do not touch the patch and do not allow anyone other than a trained medical professional to touch it. Doing so may result in dangerous or fatal overdose as large amounts of fentanyl enters the body. Do not allow others to consume this medicine. If you suspect you or someone you know has been exposed to a dangerous dose of fentanyl hydrochloride, immediately contact poison control center at 1-800-222-1222 or go to the emergency room. Respiratory depression is the most serious manifestation of fentanyl HCl overdose. Other symptoms of fentanyl hydrochloride overdose include seizure, drowsiness and slowed heart rate. If you suffer an overdose, medical personnel will remove the IONSYS patch and discontinue all opioids, while administering physical and verbal stimulation. Nurses or doctors may administer drugs to reverse the effects of fentanyl HCl, such as naloxone. They may insert an airway and administer oxygen to help you breathe. Emergency staff will monitor and maintain your body temperature, blood pressure and fluid intake.

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Because fentanyl hydrochloride is about 100 times stronger than morphine, it is of special interest to recreational drug users. The United States federal government has classified fentanyl as a Schedule II controlled opioid agonist, which means it has a high potential for abuse. Discarded IONSYS system patches may be a particular target among drug abusers because a significant portion of fentanyl remains on the system, even after maximum dosage administration.

Abusing a drug means to use it to treat symptoms without a prescription or to get high. Medical experts refer to this practice as using a drug non-medically. The Centers for Disease Control and Prevention, or CDC, states that 12 million Americans admit to using a prescription drug for non-medical purposes in 2008. Approximately 55 percent of those people got the drug free from friends or relatives in a process the DEA calls diversion. While Americans represent less than 5 percent of the world's population, it consumes 80 percent of the world's supply of pain medications.

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Because IONSSYS preparations can only be used for three consecutive days, risk for physical dependence is low. However, if you had been using opioids before surgery, there is a chance you can become dependent on fentanyl hydrochloride. Withdrawal symptoms can be overpowering, preventing you from discontinuing fentanyl hydrochloride before you leave the hospital. If have become tolerant to fentanyl hydrochloride, your physician may recommend discharge to a rehabilitation clinic before you go home. Medical specialists view withdrawal as a normal and predictable physiological response to lowering levels of a chemical on which the body has become dependent. A person experiences symptoms of withdrawal as his body tries to stabilize its blood chemistry after he has stopped taking opioids such as fentanyl. Withdrawal is a physically uncomfortable process and the flu-like symptoms of withdrawal can be overpowering enough to prevent successful rehabilitation. These withdrawal symptoms may be especially unbearable to those who have used fentanyl HCl to treat acute pain from surgery.

Withdrawal symptoms include:

  • Anxiety.
  • Diarrhea.
  • Fever, Runny Nose or Sneezing.
  • Goose Bumps and Abnormal Skin Sensations.
  • Hallucinations.
  • Insomnia.
  • Nausea or Vomiting.
  • Pain.
  • Rapid Heartbeat.
  • Rigid Muscles.
  • Shivering, Tremors.
  • Sweating.


Drug dependence is a complex medical condition requiring a multi-faceted, scientific approach. The first phase of rehabilitation includes overcoming withdrawal symptoms and detoxifying the body from the effects of fentanyl hydrochloride dependence. During standard rehabilitation, physicians administer drugs to ease uncomfortable withdrawal symptoms along with medicines to cleanse your system. This stage may take five or more days. Once you are free from the physical manifestations from chemical dependence, you may participate in counseling and other social services to help you sort out family, social or legal issues relating to your opioid use.

Rapid detox is a new, humane standard of rehabilitative care. During rapid detox, specially trained doctors administer sedatives and anesthesia alongside standard anti-withdrawal and detoxification drugs so you sleep through the worst parts of treatment. When you awaken, refreshed and revitalized, you have no recollection of the potent, uncomfortable symptoms of withdrawal.

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Fentanyl hydrochloride should be stored at 77 degrees Fahrenheit. Do not use if the foil pouch containing the fentanyl hydrochloride system is broken. Only trained medical professionals should handle, store, maintain, administer or dispose of fentanyl hydrochloride.

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Miscellaneous information

Danish Army and some military branches of the US Armed Forces use fentanyl to treat acute pain resulting from serious wounds obtained in combat. Miscellaneous Information About Fentanyl Hydrochloride