Hydrocodone Side Effects

Hydrocodone is only available by prescription and in combination with other pain relievers, such as acetaminophen or aspirin. Since hydrocodone is available only in combination with other pain relievers, such as acetaminophen, consult with the prescribing physician or pharmacist to learn about side effects associated with those additional drugs.

Individuals who become physically dependent on hydrocodone face an increased risk for side effects associated with these additives because, along with taking high or sustained doses of hydrocodone, they are consuming large amounts of other chemicals. For example, taking high doses of acetaminophen or aspirin, or using this over-the-counter medication for a long time causes liver damage.

Hydrocodone, like all drugs, has the potential to cause side effects without the additional risk posed by additives. Many consumers experience no, or very few, side effects while taking hydrocodone. Most side effects associated with hydrocodone or any additional ingredients in hydrocodone preparations are not serious and disappear after a few days. A few side effects are serious and require the attention of a medical professional.

According to the U.S. Drug Enforcement Agency, or DEA, hydrocodone is the most frequently prescribed opioid in the United States, with over 139 million prescriptions filled in 2010. Because of the euphoria hydrocodone produces, hydrocodone is associated with more drug abuse than any other opioid. The DEA says most illegal doses of hydrocodone started out as legally prescribed medication, a process known as diversion. Hydrocodone is the most widely diverted drug in the United States. Illicit hydrocodone users frequently combine this medication with alcohol, increasing the individual's risk for side effects such as toxicity, overdose and liver disease.

Potential for abuse, physical dependence or addiction are possible side effects associated with hydrocodone. The U.S. Drug Enforcement Agency, or DEA, classifies substances according to the potential for abuse. The DEA has classified hydrocodone as a Schedule II narcotic, which means it carries a high potential for abuse and mental or physical dependence.

Physical dependence means the individual will suffer withdrawal symptoms after the level of hydrocodone drops in his system, because either he has stopped taking opioids or he has taken a medication to reduce the level of hydrocodone rapidly. Withdrawal symptoms include:

  • Abdominal Cramps
  • Agitation
  • Anxiety
  • Blurred Vision
  • Insomnia
  • Restlessness
  • Sweating
  • Tremor
  • Vomiting

Overdose is a serious, potentially fatal side effect of hydrocodone. If you suspect that you or someone you know has taken an overdose of hydrocodone, contact your local emergency room or poison control center by calling 1-800-222-1222. Symptoms of overdose include:

  • Cold, Clammy or Blue Skin
  • Death
  • Excessive Sleepiness
  • Large or Small Pupils
  • Loss of Consciousness
  • Seizure
  • Slow, Shallow or Stopped Breathing
  • Slowed or Stopped Heartbeat

The adverse reactions to hydrocodone are typical of any opioids. The most serious side effect is respiratory problems potentially leading to stopped breathing, circulatory depression, dangerously low blood pressure and shock. Physicians should expect side effects in certain patients, such as the very young or very old, and treat patients accordingly. Additionally, prescribers should remain alert to signs a patient is becoming physically dependent or addicted to hydrocodone.

Some side effects are serious, requiring immediate medical attention. Stop taking this medication immediately and contact a doctor if you experience serious side effects, including:

  • Shallow Breathing
  • Slow Heartbeat
  • Feeling Lightheaded or Fainting
  • Confusion, Fear, Unusual Thoughts or Behavior
  • Seizures
  • Problems with Urination
  • Nausea, Stomach Pain, Loss of Appetite
  • Itching
  • Dark Urine, Clay-Colored Stools
  • Jaundice or Yellowing of the Skin or Eyes

The most common side effects associated with hydrocodone are not serious and disappear after taking this opioid for a few days. Continue taking hydrocodone preparations but contact the prescribing physician if the following side effects become intolerable or if they do not go away on their own:

  • Blurred Vision
  • Constipation
  • Dry mouth
  • Feeling Anxious, Dizzy or Drowsy
  • Headache
  • Mild Nausea, Vomiting, Upset Stomach
  • Mood Changes
  • Ringing in the Ears

By body system


Hydrocodone usage is associated with respiratory depression. Respiratory depression is a condition where the lungs do not adequately exchange oxygen and carbon dioxide. Respiratory depression, characterized by slow or shallow breathing, can be fatal.

Nervous System

Hydrocodone may cause side effects in the nervous system, such as dizziness, lightheadedness, stupor or extreme sleepiness. Hydrocodone can also cause mood disorders, such as mental depression, delirium, agitation, and dysphoria, or sadness.

Hepatic System

Hydrocodone may cause side effects in the liver and gallbladder, otherwise known as the hepatic system. Adverse reactions to hydrocodone may be more common or severe in patients with liver disease. Hydrocodone preparations frequently contain acetaminophen, which causes liver damage when taken in high doses or for a long time. An individual dependent on hydrocodone may inadvertently consume large amounts of acetaminophen and cause liver damage that increases risk for adverse reactions associated with hydrocodone. Additionally, abusers of hydrocodone frequently consume this drug along with alcohol, also associated with an increased risk for liver damage. Fasting increases the risk for serious liver damage, especially in alcoholic patients.

Gastrointestinal and Genitourinary

Hydrocodone causes gastrointestinal side effects typical of other opioid pain relievers. These side effects include nausea, vomiting, constipation and a dry mouth. Hydrocodone is associated with genitourinary side effects such as spasm of the urethra or vesicle sphincters and urinary retention.


Hydrocodone may cause narcotic-induced rashes. Using hydrocodone-acetaminophen combination products increases the risk for red skin rashes, although this condition is rare.


The risks for suffering adverse reactions from hydrocodone are higher in patients with renal insufficiency, a type of kidney disease. Some types of kidney diseases occur in conjunction with liver failure, which may arise in alcoholics or addicts who use hydrocodone preparations containing acetaminophen. An individual faces a higher risk for kidney damage after overdose, from chronic abuse of hydrocodone or other analgesics, or from liver damage associated with acetaminophen use.


The risk for hematologic side effects, or adverse blood reactions, is associated mainly with additive analgesics, such as acetaminophen. Rarely, acetaminophen causes the blood-clotting problem known as thrombocytopenia.