+ -Text Size



Trade/other name(s): Dilaudid, Dilaudid HP, Exalgo

Why would this drug be used?

Hydromorphone is a strong pain medicine (an opioid analgesic) that is used to relieve moderate to severe pain.

The slow-release form of hydromorphone is only used for long-term (chronic) pain. Before starting to take it, the person must have already gotten used to taking opioid pain medicines such as morphine, fentanyl, or oxycodone, and have taken them every day for at least a week.

How does this drug work?

Hydromorphone is an opioid pain reliever, similar to morphine. It binds to opioid receptors in the brain and central nervous system (CNS), reducing the perception of pain as well as the emotional response to pain.

Before taking this medicine

Tell your doctor…

  • If you are allergic to anything, including medicines, dyes, additives, or foods.
  • If you have any medical conditions such as kidney disease, liver disease (including hepatitis), low thyroid function, or Addison’s disease (low adrenal function). These conditions may require that your medicine dose, regimen, or timing be changed.
  • If you have abdominal pain or any disorder with slowed or blocked intestines, such as paralytic ileus, you shouldn’t take hydromorphone. If you’ve had this kind of problem in the past, tell your doctor so that you can be watched in case it comes back.
  • If you have trouble passing urine, a narrow urethra, or if you have an enlarged prostate. Hydromorphone can make it harder to urinate.
  • If you have ever had a seizure, head injury, or if you have had problems with pressure, infection, or a tumor in your head or brain. Hydromorphone can raise your risk of seizures.
  • If you have low blood pressure. Hydromorphone can worsen this.
  • If you have asthma, emphysema, chronic bronchitis, sleep apnea, or another breathing problem. Hydromorphone can make it worse and even cause breathing to stop.
  • If you have gallstones, gallbladder disease, or pancreatitis. Hydromorphone can sometimes worsen these problems.
  • If you have taken monoamine oxidase inhibitors (MAOIs) within the past 2 weeks (see “Interactions with other drugs”). Hydromorphone can cause slow or shallow breathing, low blood pressure, excitability, seizures, coma, or shock if any MAOI is left in the body.
  • If you are planning to have surgery or anything requiring general anesthesia in the near future. (See also “Precautions.”)
  • If you drink alcohol or take any medicine that can affect your brain or nervous system. These can increase the risk of harmful effects, including the risk of death, or cause other problems.
  • If you have trouble with addiction, alcohol, or drug abuse now or have had one in the past. Hydromorphone can be habit forming, especially for those who have had problems before.
  • If you have never taken opioid pain relievers before. Only people who have taken opioid pain medicines each day for at least the past week should take time-release hydromorphone.
  • If you have serious mental illness or have ever had delirium tremens (severe alcohol withdrawal symptoms). You may have more problems on hydromorphone.
  • If any family members have or have had an addiction or drug problem. Hydromorphone is sometimes stolen by or for those who have become addicted to it or drugs like it.
  • If you are pregnant, trying to get pregnant, or if there is any chance of pregnancy. There may be an increased risk of harm to the fetus if a woman takes this drug during pregnancy, especially later in pregnancy (see the “Precautions” section).
  • If you are breastfeeding. The drug passes into breast milk and can affect the baby.
  • About all other prescription or over-the-counter medicines you are taking, including vitamins and herbs. In fact, keeping a written list of each of these medicines (including the doses of each and when you take them) with you in case of emergency may help prevent complications if you get sick.

Interactions with other drugs

Buprenorphine (Subutex, Suboxone), butorphanol (Stadol), nalbuphine (Nubain), or pentazocine (Talwin, Talacen) may decrease the effects of hydromorphone or stop its action altogether. This can cause withdrawal symptoms if you have taken hydromorphone for some time.

Antidepressants of the older monoamine oxidase inhibitor (MAOI) type such as phenelzine (Nardil), tranylcypromine (Parnate), isocarboxazid (Marplan), or selegiline (Emsam) may cause slow or shallow breathing, low blood pressure, excitability, seizures, shock, or even coma if hydromorphone is given within 2 weeks of the last MAOI dose.

Medicines or substances that slow down the brain or nervous system, such as these, can cause worse side effects if taken with hydromorphone:

  • Anti-anxiety drugs (tranquilizers or sedatives)
  • Sleeping pills
  • Muscle relaxers
  • Barbiturates
  • Anti-seizure medicines
  • Other opioid drugs
  • Anesthetics
  • Tricyclic antidepressants such as amitriptyline (Elavil), nortriptyline (Pamelor), imipramine (Tofranil), desipramine (Norpramin), doxepin (Sinequan), and others
  • Anti-psychotic drugs
  • Certain anti-nausea medicines
  • Certain antihistamines (those that cause sleepiness)
  • Alcohol-containing drugs or beverages, including beer, wine, and mixed drinks

Some of these can cause slowed breathing, low blood pressure, extreme sleepiness, coma, or even death if taken with hydromorphone.

Check with your doctor, nurse, or pharmacist about whether other medicines, vitamins, herbs, and supplements can cause problems with this medicine.

Interactions with foods

Beverages that contain alcohol, including beer, wine, and mixed drinks, can raise the risk of harmful effects and death if taken while you’re being treated with hydromorphone.

No other serious interactions with food are known at this time. Check with your doctor, nurse, or pharmacist about whether foods may be a problem.

Tell all the doctors, dentists, nurses, and pharmacists you visit that you are taking this drug.

How is this drug taken or given?

Hydromorphone can be given by mouth as a pill or a liquid, or as a rectal suppository. It can also be given as an injection under the skin or in a vein as a short infusion or a continuous infusion with extra medicine that you can take when needed (patient controlled analgesia or PCA). Your doctor may start you on a low dose and slowly increase it over a few days or weeks. The dose will depend on how you respond to the drug, and how well the medicine controls your pain.

The pill and liquid should be taken with a full glass of water. You should shake the liquid before measuring the dose. If it upsets your stomach, take it with food.

If you are taking the extended-released pill (Exalgo), swallow it whole. Do not crush, chew, split, break, melt, or dissolve it. The pills contain enough medicine for the whole day. If they are chewed, dissolved, or crushed, the entire dose can be absorbed by the body all at once, causing overdose symptoms such as trouble breathing and even death. Try to take your dose at the same time each day.

When taking a suppository, open the package and then dip the tip in water. If you are right-handed, lie down on your left side, bring your knees up near your chest, and slowly insert the suppository in your rectum about an inch. You should stay in this position for about 15 minutes, then get up and wash your hands well.

Take this drug exactly as directed by your doctor. If you do not understand the instructions, ask your doctor or nurse to explain them to you.

Store the medicine in a tightly closed container away from heat and moisture and safely away from children, pets, and other people. Flush medicine that you do not plan to use down the toilet. Do not let others take your medicine.


This medicine can cause drowsiness and lightheadedness. Do not drive, operate machinery, or perform other activities that require alertness until you know how you react to this medicine.

Hydromorphone can make you feel dizzy or faint, and increase your risk of falling. Be careful getting up, changing position, or walking. Get up slowly and hold onto something or someone to keep you steady. If you feel lightheaded or dizzy, it may help to lie down. It is best to have a responsible adult with you for the first day or two after starting the hydromorphone or after any increase in dose, until you know how you will respond to it.

Since hydromorphone affects the central nervous system, do not take other drugs or substances that slow down the brain or nervous system such as alcohol, sedatives, muscle relaxers, and sleeping medicines unless your doctor tells you to do so (see “Interactions with other drugs”).

Call your doctor right away if you have trouble breathing, get short of breath, dizzy, faint, confused, feel very drowsy, or start seeing or hearing things that aren’t there. These may be signs your dose is too high, or you could have gotten an accidental overdose of the medicine.

Tell your doctor or nurse right away if you have trouble passing urine, trouble walking, vision problems, fainting, trouble swallowing, or other problems.

If you are having any kind of surgery or dental procedure, be sure to tell the doctor or dentist in charge that you are using this medicine. Some anesthetic drugs can cause a dangerous drop in blood pressure if hydromorphone is in your system.

Constipation is a very common side effect of taking opioid pain medicines. While you're taking hydromorphone, your doctor may advise you to take medicines such as stool softeners, bulk-forming agents, and/or laxatives as needed to have regular (daily) bowel movements. Talk to your nurse or doctor about this when you first start this medicine. Drink plenty of fluids throughout the day, and try to eat foods high in fiber such as whole grains, bran, fruits, and vegetables. Call your doctor or nurse right away if you have not moved your bowels in 2 days.

Most cancer pain can be controlled. Tell your cancer team if your medicines do not control your pain, and keep them informed about any side effects you are having. Your cancer team may need to adjust your medicines several times before they find the medicines that work best for you.

If you have chronic (long-term) cancer pain, talk to your doctor about taking your pain medicines on a regular schedule to keep it from worsening. If you wait until the pain is bad, it takes more medicine to get it under control. If pain comes back between doses, talk to your cancer team about changing your medicine or adding an extra one for “breakthrough” pain.

Talk to your doctor or nurse about using the smallest effective dose to reduce side effects and the development of tolerance and physical dependence. Tolerance means that larger doses needed to give the same pain relief. Physical dependence means that the body goes into withdrawal if drug is suddenly stopped. Both of these happen normally when strong opioid medicines are taken over several weeks to treat chronic pain. But this is different from addiction, which starts when the drug is taken for pleasure, not for pain relief. Tell your doctor or nurse if you still have pain despite taking the medicine as directed. Do not adjust your dose without talking to your doctor or nurse first.

Do not stop taking this medicine without talking to your doctor or nurse. When no longer needed, this medicine should be stopped gradually with the help of your doctor. If it is stopped too quickly or the dose reduced too much, you can have withdrawal symptoms such as restlessness, irritability, anxiety, runny nose, watering eyes, yawning, sweating, chills, gooseflesh, aches, nausea, vomiting, diarrhea, poor appetite, high blood pressure, fast heartbeat, and fast breathing.

Acetaminophen or aspirin are often taken along with hydromorphone to increase the pain relief action. It is important to know if any of your other medicines contain either of these drugs. They are in many other remedies, and it is easy to accidentally get too much of them. Check with your doctor, nurse, or pharmacist to find out which of these drugs are included in your daily medicines.

Using opioid drugs such as hydromorphone during pregnancy, especially near the end of the pregnancy, can cause neonatal opioid withdrawal. This can be life-threatening to a newborn if it’s not recognized and treated.

This drug is a controlled substance, and may be habit forming. Keep your medicine in a safe place, away from other people, and do not let anyone else take your medicine. A person who has taken hydromorphone for a long time often needs large doses for pain relief, while the same amount could quickly kill someone else.

If you think you or someone else may have taken an overdose of hydromorphone, or if someone else has taken even one dose of time-release hydromorphone, get emergency help right away. Symptoms of hydromorphone overdose may include extreme drowsiness, slow heartbeat, slow or irregular breathing, cold clammy skin, or coma. Hydromorphone overdose may cause the heart or breathing to stop.

Possible side effects

You will probably not have most of the following side effects, but if you have any talk to your doctor or nurse. They can help you understand the side effects and cope with them.


  • Constipation*
  • Drowsiness*
  • Sedation*
  • Dizziness, lightheadedness*
  • Nausea
  • Dry mouth
  • Sweating

Less common

  • Mood changes, such as euphoria (happiness)
  • Mental clouding
  • Slow or shallow breathing*
  • Vomiting
  • Slowed digestion
  • Low blood pressure (can cause you to be dizzy or faint when sitting or standing)*
  • Slow heart rate
  • Headache
  • Itching


  • Seizures
  • Trouble urinating*
  • Decreased sexual interest
  • Impotence
  • Bowel rupture due to constipation*
  • Allergic reaction
  • Opioid withdrawal and even death in the newborn if it’s taken during pregnancy*
  • Death due to overdose, low blood pressure, slow/shallow breathing, bowel rupture, drug interaction, or other causes*

*See “Precautions” section for more detailed information.

There are some other side effects not listed above that can also occur in some patients. Tell your doctor or nurse if you develop these or any other problems.

FDA approval

Yes – first approved in 1984.

Disclaimer: This information does not cover all possible uses, actions, precautions, side effects, or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for talking with your doctor, who is familiar with your medical needs.

Last Medical Review: 06/18/2014
Last Revised: 06/18/2014