Referred pain of renal colic from posterior and anterior views
The classic presentation of a patient with renal colic is writhing in pain and unable to remain in a still position. This is in contrast to a patient with abdominal pain from another origin that typically remains motionless in order to minimize discomfort.
Pain control in renal colic can be achieved with a variety of medications. After the diagnosis of obstructive renal colic is made, the severity of pain will determine the type of medication that the patient should receive. Intravenous pain medication will be needed for severe pain related to renal colic while oral medications should be reserved for patients without the need for surgical intervention as an outpatient.
The ultimate goal of the pain therapy is to allow the patient to tolerate the symptoms until definitive treatment can be performed. Several types of medications can be utilized before and after surgery to help alleviate the pain.
In the following pages we have a first-hand account from a patient that suffered with renal colic and what their experience entailed when they required urgent care. We will then review the various medications that are used to treat the pain associated with renal colic noting the strengths as well as limitations of each. We will also review some common misconceptions associated with these pain medications. Lastly, we will review some commonly asked questions with regard to pain associated with renal colic and the medications used to treat the pain.
What were your first symptoms?
For a long time I’d noticed small streaks of blood in my urine. Then 1 day I felt a sharp pain in my side and my belly.
Describe the pain you felt.
It was really sharp, it felt like someone cutting me on the inside with a sharp knife. It was mostly in my side but also went down to my lower belly and my groin.
Did you try anything to treat the pain? Did any of it help?
I tried antacids, aspirin, but none of it helped. I tried drinking lots of water also, but that only made the pain more frequent because I had to go to the bathroom more often. The pain would last for a while then go away on it’s own, but would come back later.
What made you seek medical attention?
When the pain persisted for days and I couldn’t control it anymore I felt I had to have it treated. It was the worst pain I have ever felt.
When you came to the hospital, what happened? How did you feel at that time?
The first thing they did in the emergency room was place an intravenous line and give me fluids. They also gave me some morphine for the pain, it helped take some of the pain away, but it came back very soon. They also told me that I couldn’t have anything to eat or drink.
What tests did they run?
They did blood tests and urine tests, my urine had small amounts of blood in it, so they did an ultrasound of my side and my bladder. Then they sent me for a CT scan which showed that I have a stone in my urinary system. The doctors said I needed a stent to help urine bypass the stone.
What were your concerns at that time?
My biggest concern was finding relief from my pain, but I was also nervous about the procedure because it sounded like it would be painful.
What was your experience during the procedure? Was it painful?
I don’t remember the procedure very much, I was given sedative medication prior to the procedure and was sleeping for most of it. I don’t remember any pain during the procedure.
How did you feel immediately after and a few days after the procedure? Were you still in pain?
Immediately after I was very sleepy from the anesthesia, I didn’t feel any pain at that time. Once the anesthesia wore off I felt fine. After I left the hospital I had more pain in my side, it was crampy and came in waves. My urologist gave me a pain pill call Percocet as well as Myrbetriq which helped, but it only completely went away after the stent was removed.
Opioid medications provide very effective and reliable pain relief for patients experiencing acute to pain (See Table 1). Pain experienced by patients with renal colic is classified in this manner. Chronic opiate use remains a controversial topic however with very little to no available medical evidence. These medications work on opioid receptors located predominantly in the brain and spinal cord to decrease pain intensity. Opioids are an attractive treatment option for a practitioner due to their clinical predictability, multiple routes of administration (i.e. oral, intravenous, rectal, etc.), and effectiveness in the acute pain setting. Side effects include pruritus, nausea, constipation, urinary retention, sedation, and respiratory depression among others. Other considerations when prescribing opioids include the risk of dependence, abuse, withdrawal and diversion. For this reason, it is important to counsel the patient on opioid safety and risks when initiating opioid therapy for outpatient use. Inpatient opioid administration should be done with careful monitoring, especially in opioid naïve patients. We will explore some of the more commonly used opiates for use in the management of renal colic below.
Common opiates used in renal colic
MSIR, MS Contin, etc.
5–30 mg 4×/day orally
Variable IV dosing
2–4 mg 4×/day
Variable IV dosing
15–60 mg 6×/day
50–150 mg 6×/day
5–10 mg 3–4×/day
50–100 mg 3×/day
5–10 mg 3–4×/day
Morphine is the “gold standard” with regard to opioid medications. All other opioid potencies are compared to that of morphine. It is available in a variety of formulations including intravenous and oral formulations which are the most commonly used for renal colic. For intravenous morphine dosing is typically 2–5 mg to start every 5 min to achieve adequate analgesia. The onset of action is typically 5–10 min. Metabolism is via the liver resulting in active metabolites that are renally excreted. This can result in unwanted accumulation and significant side effects in patients who have impaired renal function due to their renal disease .
Hydromorphone (Dilaudid) is a more potent opioid than morphine with equianalgesic ratios of approximately 1.5 mg of hydromorphone being equivalent to approximately 10 mg of morphine. Dosing is started at 0.2–1 mg intravenously every 2–3 hours. Hydromorphone typically starts working in 5 min but takes 10–20 min to take full effect. Metabolism is via the liver with non-active metabolites excreted by the kidneys. Oral formulations are available for outpatient use but should be reserved for patients who are opioid tolerant and are already on oral hydromorphone .
Meperidine (Demerol) was the first synthetically produced opioid analgesic. It’s use has been falling out of favor in recent years due to its significant side effects. Meperidine is metabolized by the liver to normeperidine. This active metabolite has approximately half of the analgesic effect of meperidine but two to three times the central nervous system effects. In addition, normeperidine has a half-life of 15–30 hours, much longer than the 2.5–4 hours half-life of meperidine. Accumulation of this metabolite can occur with doses greater than 600 mg per day as well as in patients with renal dysfunction. The central nervous system effects can range from irritability and muscle twitching to hallucinations and seizures. For these reasons, along with high abuse potential, it is not recommended that meperidine be used for pain control in the setting of renal colic .
Oxycodone (ex. Roxicodone) commonly prescribed for management of pain and is available in both a pill and as a liquid either by itself, or in combination with acetaminophen (Perocet, Endocet, Roxicet). Onset of action is within 15 min and lasts 3–6 hours. Dosing is typically 5–10 mg every 4–6 hours as needed. It is important to note that patients may want to take higher or more frequent doses but limitations on the maximum amount of acetaminophen (3 g per day in healthy adults) should be taken into account .
Tramadol (Ultram) exhibits weak opioid receptor agonist properties as well as inhibition of the reuptake of norepinephrine and serotonin. Onset of action is within an hour and lasts approximately 9 hours. Typical doses are 50–100 mg every 4–6 hours. Metabolism is via the liver and excreted by the kidneys. For this reason, it is important to remember to reduce the dose in patients with significant renal disease .