What's in Your IV Pain Meds?

The Differences Between Commonly Used IV Pain Medications

A variety of medications are frequently used in the hours and days after surgery to control pain. Pain is typically the most severe in the 72 hours after surgery, which, unsurprisingly, is when patients are most likely to receive potent pain relievers.

Nurse setting up IV
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Most medications to relieve pain are given as a pill or intravenously (through an IV). These medications may be a non-steroidal anti-inflammatory (NSAID) in the same drug family as ibuprofen, or they may be an opioid-based narcotic medication, such as morphine.

The term opioid refers to the origins of the medication in the poppy plant, from which opium is derived. You may also hear pain medications referred to as analgesics, this is a term used to describe a medication used for pain relief.

Why IV Pain Medication Is Used

In the initial hours following surgery, the patient may still be under the influence of anesthesia, and it isn’t safe to take oral medications until they are awake enough to swallow without choking.

If a patient is awake and well enough to tolerate drinking fluids, their medication will typically be given in a pill form, unless the pain is poorly controlled by oral medications. If the patient cannot take pain medication as a pill, or they need a medication that will work very quickly, IV pain medication may be given.

Many pain medications are available as both a pill or an injection into an IV. Some are available in a syrup, a patch or a medication that is placed under to tongue to be absorbed.

The main benefit to IV pain medication over other forms of medication is that it typically takes effect very quickly, often within minutes because it is moving directly into the bloodstream.

Once discharged from the hospital, it isn’t practical to use IV pain medications, as most individuals do not return home with an IV site in place, and pills or another form of non-IV medication will typically be prescribed.

Common IV Pain Medications

  • Toradol (Ketorolac): This medication is in the NSAID family, and it used to treat mild to moderate pain, it also has anti-inflammatory effects.
  • Ofirmev (Acetaminophen): This medication, an NSAID, is essentially IV Tylenol. It is used as a fever-reducing agent that also can treat mild pain.
  • Caldolor (Ibuprofen): This medication, also an NSAID, is basically IV Advil. It is used to reduce mild to moderate pain, inflammation and has some ability to reduce fever.
  • Morphine: A narcotic pain reliever, morphine is used to reduce moderate to severe pain. Morphine is frequently used for both acute pain and long-term chronic pain.
  • Dilaudid (Hydromorphone): A narcotic pain reliever, Dilaudid is very potent and is used to treat severe pain after surgery.
  • Fentanyl: This medication is a synthetic opioid, meaning that it is man-made and not made from the poppy plant like other narcotic medications. It is used to control severe pain after surgery.
  • Demerol: This medication, an opioid analgesic, is no longer used as frequently as it was in the past. Demerol is less likely to control pain and more likely to cause euphoria and delirium than other types of pain medication. It is occasionally used off-label (outside of typical use) to help decrease shivering in patients who are being cooled, due to fever or the need for hypothermia as a treatment, but it's no longer routinely used for control of surgical pain.

Risks of Prescription Pain Medication

Pain medications used after surgery have a number of possible risks and side effects:

  • Sedative Effects: These effects range from the mild (feeling sleepy) to severe (not breathing). Due to the risk of sedation, these medications should not be taken when operating a car. Take pain medication as directed to avoid an unintentional overdose.
  • Constipation: All narcotics, whether they are given as a pill or an injection, are known to cause constipation. Many patients take a stool softener daily to prevent constipation when taking narcotic pain medication.
  • Addiction: Inappropriate and/or extended use of narcotics can lead to a physical and mental addiction. Narcotic pain relievers should not be taken any longer than absolutely necessary.
  • Nausea/Vomiting: Some individuals don’t tolerate this type of medication well and it causes nausea and vomiting. For some, pre-medicating with an anti-nausea medication such as Zofran (ondansetron) or Phenergan may prevent or reduce these symptoms.
  • Itching: Prescription pain relievers are well known to cause itching.For some, changing to different pain medication will provide relief, others require a medication known to reduce itching such as Benadryl or prescription Vistaril.
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By Jennifer Whitlock, RN, MSN, FN
Jennifer Whitlock, RN, MSN, FNP-C, is a board-certified family nurse practitioner. She has experience in primary care and hospital medicine.