III. Other Drugs

Objectives:

• Identify the three major types of drugs.
• List one example of each type of drug, and describe how it affects the body.
• Explain the difference between physical and psychological addiction.
• Identify the difference between prescription and nonprescription drugs.
  

Medical Uses of Drugs

Both prescription and non-prescription drugs are designed to improve the health care of people with medical conditions. Some drugs can be purchased without a prescription. These are called over-the-counter drugs.  These are drugs such as Tylenol, aspirin, or ibuprofen which are used for pain.  Other drugs used for cough and cold such as Sudafed or Robitussin are also over the counter.  These drugs could be dangerous if taken inappropriately.  The consumer must follow the directions on the label.

Prescription drugs are those drugs that can be obtained only by a physician.  These drugs can only by obtained from a pharmacist.   The medication should be taken as prescribed by the physician. 

Alone, many prescription and nonprescription drugs impair the ability to drive a motor vehicle. 

Drug Addiction

Physical dependence refers to a state resulting from chronic use of a drug that has produced tolerance and where negative physical symptoms of withdrawal result from abrupt discontinuation or dosage reduction.  Physical dependence can develop from low-dose therapeutic use of certain medications as well as misuse of recreational drugs such as alcohol.

Psychological dependency is a dependency of the mind, and leads to psychological withdrawal symptoms (such as cravings, irritability, insomnia, depression, anorexia, etc.

Summary:

1. Alone, many prescription and nonprescription drugs impair the ability to drive a motor vehicle. 
2. The consumer must follow the directions on the label of an over the counter medication.
3. Physical dependence can develop from low-dose therapeutic use of certain medications as well as misuse of recreational drugs such as alcohol.

Effects of Drugs

What are opioids?

Opioids are medications that act on opioid receptors in both the spinal cord and brain to reduce the intensity of pain-signal perception. They also affect brain areas that control emotion, which can further diminish the effects of painful stimuli. They have been used for centuries to treat pain, cough, and diarrhea.²⁸ The most common modern use of opioids is to treat acute pain. However, since the 1990s, they have been increasingly used to treat chronic pain, despite sparse evidence for their effectiveness when used long term.²⁹ Indeed, some patients experience a worsening of their pain or increased sensitivity to pain as a result of treatment with opioids, a phenomenon known as hyperalgesia.³⁰

Importantly, in addition to relieving pain, opioids also activate reward regions in the brain causing the euphoria—or high—that underlies the potential for misuse and substance use disorder. Chemically, these medications are very similar to heroin, which was originally synthesized from morphine as a pharmaceutical in the late 19th century.³¹ These properties confer an increased risk of substance use disorder even in patients who take their medication as prescribed.²⁹

Overdose is another significant danger with opioids, because these compounds also interact with parts of the brain stem that control breathing. Taking too much of an opioid can suppress breathing enough that the user suffocates. An overdose can be reversed (and fatality prevented) if the compound naloxone is administered quickly.

Prescription opioid medications include hydrocodone (e.g., Vicodin^®), oxycodone (e.g., OxyContin^®, Percocet^®), oxymorphone (e.g., Opana^®), morphine (e.g., Kadian^®, Avinza^®), codeine, fentanyl, and others. Hydrocodone products are the most commonly prescribed in the United States for a variety of indications, including dental- and injury-related pain.³² Oxycodone and oxymorphone are also prescribed for moderate to severe pain relief.^33,34 Morphine is often used before and after surgical procedures to alleviate severe pain, and codeine is typically prescribed for milder pain.²⁸ In addition to their pain-relieving properties, some of these drugs—codeine and diphenoxylate (Lomotil^®), for example—are used to relieve coughs and severe diarrhea.²⁸