Pain Medications and Other Prescription Drugs
Medications used to treat pain
include:
1.
Narcotics ñ
Also known as opioids.
2.
Muscle
relaxants
3.
Anti-inflammatory
medications
a.
Steroids
b.
Non-steroidal
anti-inflammatory medications
4.
Anticonvulsants
5.
Antidepressants
6.
Local
anesthetics (Numbing medicines)
7.
Anti-hypertensives
(Blood pressure medicine)
8.
Over-the-counter
medications
Prescription
drugs make complex surgery possible, relieve pain for millions of people, and
enable many individuals with chronic medical conditions to control their
symptoms and lead productive lives. Most people who take prescription
medications use them responsibly. However, the non-medical use of prescription
drugs is a serious public health concern. Non-medical use of prescription drugs
like opioids, central nervous system (CNS) depressants, and stimulants can lead
to abuse and addiction, characterized by compulsive drug seeking and use.
Addiction
rarely occurs among people who use a pain reliever, CNS depressant, or
stimulant as prescribed; however, inappropriate use of prescription drugs can
lead to addiction in some cases. Patients, healthcare professionals, and
pharmacists all have roles in preventing misuse and addiction. For example, if
a doctor prescribes a pain medication, CNS depressant, or stimulant, the
patient should follow the directions for use carefully, and also learn what
effects the drug could have and potential interactions with other drugs by
reading all information provided by the pharmacist. Physicians and other health
care providers should screen for any type of substance abuse during routine
history-taking with questions about what prescriptions and over-the-counter
medicines the patient is taking and why.
In
1999, an estimated 4 million people, about 2 percent of the population age 12
and older, were using prescription drugs for non-medical reasons. Of these, 2.6
million misused pain relievers, 1.3 million misused sedatives and
tranquilizers, and 0.9 million misused stimulants.1
Data suggest that up to 17 percent of adults age 60 or older may be abusing
prescription drugs. Older people are prescribed medications about three times
more frequently than the general population, and have poorer compliance with
directions for use.
While
many prescription drugs can be abused or misused, these three classes are most
commonly abused:
Opioids
are commonly prescribed because of their effective analgesic or pain relieving
properties. Many studies have shown that properly managed medical use of opioid analgesic drugs is safe and rarely causes clinical
addiction, which is defined as compulsive, often uncontrollable use. Taken
exactly as prescribed, opioids can be used to manage pain effectively.
Among
the drugs that fall within this class - sometimes referred to as narcotics -
are morphine, codeine, and related drugs. Morphine is often used before or
after surgery to alleviate severe pain. Codeine is used for milder pain. Other
examples of opioids that can be prescribed to alleviate pain include oxycodone (OxyContin-an oral,
controlled release form of the drug); propoxyphene (Darvon, Darvocet); hydrocodone (Vicodin); hydromorphone (Dilaudid); and meperidine (Demerol), which is used less often because of
its side effects. In addition to their effective pain relieving properties,
some of these drugs can be used to relieve severe diarrhea (Lomotil,
for example, which is diphenoxylate) or severe coughs
(codeine).
Opioids
act by attaching to specific proteins called opioid
receptors, which are found in the brain, spinal cord, and gastrointestinal
tract. When these drugs attach to certain opioid
receptors in the brain and spinal cord they can effectively block the
transmission of pain messages to the brain.
In
addition to relieving pain, opioid drugs can affect
regions of the brain that mediate what we perceive as pleasure, resulting in
the initial euphoria that many opioids produce. They can also produce
drowsiness, cause constipation, and, depending upon
the amount of drug taken, depress breathing. Taking a large single dose could
cause severe respiratory depression or be fatal.
Opioids
may interact with other drugs and are only safe to use with other drugs under a
physician's supervision. Typically, they should not be used with substances
such as alcohol, antihistamines, barbiturates, or benzodiazepines. These drugs
slow down breathing, and their combined effects could risk life-threatening
respiratory depression.
Chronic
use of opioids can result in tolerance to the drugs so that higher doses must
be taken to obtain the same initial effects. Long-term use also can lead to
physical dependence - the body adapts to the presence of the drug and
withdrawal symptoms occur if use is reduced abruptly.
Symptoms
of withdrawal can include restlessness, muscle and bone pain, insomnia,
diarrhea, vomiting, cold flashes with goose bumps ("cold turkey"),
and involuntary leg movements.
Options
for effectively treating addiction to prescription opioids are drawn from
experience and research on treating heroin addiction. Some examples follow.
Methadone,
a synthetic opioid that blocks the effects of heroin
and other opioids, eliminates withdrawal symptoms, and relieves drug craving.
It has been used for over 30 years to successfully treat people addicted to
opioids.
Other
medications include LAAM (levo-alpha-acetyl-methadol),
an alternative to methadone that blocks the effects of opioids for up to 72
hours. Naltrexone is a long acting opioid blocker often used with highly motivated individuals
in treatment programs promoting complete abstinence, and also to prevent
relapse.
Buprenorphine,
another synthetic opioid, will soon be available.
Also, naloxone counteracts the effects of opioids and
is used to treat overdoses.
CNS
depressants slow down normal brain function. In higher doses, some CNS
depressants can become general anesthetics.
CNS
depressants can be divided into two groups, based on their chemistry and
pharmacology:
There
are many CNS depressants, and most act on the brain similarly - they affect the
neurotransmitter gamma-aminobutyric acid (GABA).
Neurotransmitters are brain chemicals that facilitate communication between
brain cells. GABA works by decreasing brain activity. Although different
classes of CNS depressants work in unique ways, ultimately it is their ability
to increase GABA activity that produces a drowsy or calming effect. Despite
these beneficial effects for people suffering from anxiety or sleeping
disorders, barbiturates and benzodiazepines can be addictive and should be used
only as prescribed.
CNS
depressants should not be combined with any medication or substance that causes
sleepiness, including prescription pain medicines, certain over-the-counter cold
and allergy medications, or alcohol. The effects of the drugs can combine to
slow breathing, or slow both the heart and respiration, which can be fatal.
Discontinuing
prolonged use of high doses of CNS depressants can lead to withdrawal. Because
they work by slowing the brain's activity, a potential consequence of abuse is
that when one stops taking a CNS depressant the brain's activity can rebound to
the point that seizures can occur. Someone thinking about ending their use of a
CNS depressant, or who has stopped and is suffering withdrawal, should speak
with a physician and seek medical treatment.
In
addition to medical supervision, counseling in an in-patient or out-patient
setting can help people who are overcoming addiction to CNS depressants. For example,
cognitive-behavioral therapy has been used successfully to help individuals in
treatment for abuse of benzodiazepines. This type of therapy focuses on
modifying a patient's thinking, expectations, and behaviors while
simultaneously increasing their skills for coping with various life stressors.
Often
the abuse of CNS depressants occurs in conjunction with the abuse of another
substance or drug, such as alcohol or cocaine. In these cases of polydrug abuse, the treatment approach needs to address the
multiple addictions.
Stimulants
are a class of drugs that enhance brain activity - they cause an increase in
alertness, attention, and energy that is accompanied
by increases in blood pressure, heart rate, and respiration.
Historically,
stimulants were used to treat asthma and other respiratory problems, obesity,
neurological disorders, and a variety of other ailments. As their potential for
abuse and addiction became apparent, the use of stimulants began to wane. Now,
stimulants are prescribed for treating only a few health conditions, including
narcolepsy, attention-deficit hyperactivity disorder (ADHD), and depression
that has not responded to other treatments. Stimulants may also be used for
short-term treatment of obesity, and for patients with asthma who do not
respond to other medications.
Stimulants
such as dextroamphetamine (Dexedrine) and
methylphenidate (Ritalin) have chemical structures that are similar to key
brain neurotransmitters called monoamines, which include norepinephrine
and dopamine. Stimulants increase the levels of these chemicals in the brain
and body. This, in turn, increases blood pressure and heart rate, constricts
blood vessels, increases blood glucose, and opens up the pathways of the
respiratory system. In addition, the increase in dopamine is associated with a
sense of euphoria that can accompany the use of these drugs.
Research
indicates that people with ADHD do not become addicted to stimulant
medications, such as Ritalin, when taken in the form prescribed and at treatment
dosages.5 However, when misused, stimulants
can be addictive.
The
consequences of stimulant abuse can be extremely dangerous. Taking high doses
of a stimulant can result in an irregular heartbeat, dangerously high body
temperatures, and/or the potential for cardiovascular failure or lethal
seizures. Taking high doses of some stimulants repeatedly over a short period
of time can lead to hostility or feelings of paranoia in some individuals.
Stimulants
should not be mixed with antidepressants or over-the-counter cold medicines
containing decongestants. Anti-depressants may enhance the effects of a
stimulant, and stimulants in combination with decongestants may cause blood
pressure to become dangerously high or lead to irregular heart rhythms.
Treatment
of addiction to prescription stimulants, such as methylphenidate and
amphetamines, is based on behavioral therapies proven effective for treating
cocaine or methamphetamine addiction. At this time, there are no proven
medications for the treatment of stimulant addiction. Antidepressants, however,
may be used to manage the symptoms of depression that can accompany early
abstinence from stimulants.
Depending
on the patient's situation, the first step in treating prescription stimulant
addiction may be to slowly decrease the drug's dose and attempting to treat
withdrawal symptoms. This process of detoxification could then be followed with
one of many behavioral therapies. Contingency management, for example, uses a
system that enables patients to earn vouchers for drug-free urine tests; the
vouchers can be exchanged for items that promote healthy living.
Cognitive-behavioral therapies are proving beneficial, and recovery support
groups may also be effective in conjunction with a behavioral therapy.
Reference - National Institute on Drug Abuse, Research Report
Series: Prescription Drugs/Abuse and Addiction, April 2001.
1 These data are from
the 1999 National Household Survey on Drug Abuse (NHSDA), funded by the
Substance Abuse and Mental Health Services Administration (SAMHSA). NHSDA is an
annual survey on the nationwide prevalence and incidence of illicit drug,
alcohol, and tobacco use among Americans age 12 and older. The 1999 NHSDA also
provides estimates of State and
2 The Monitoring the
Future (MTF) survey is conducted by the
3 L. Simoni-Wastila, The Use of Abusable
Prescription Drugs: The Role of Gender, Journal of Women's Health and
Gender-based Medicine 9(3):289-297, 2000.
4 The latest findings
on drug abuse related hospital visits (emergency room data) and deaths (medical
examiner data) are from the 1999 Drug Abuse Warning Network (DAWN), produced by
the Substance Abuse and Mental Health Services Administration (SAMHSA). For
detailed information from of the latest survey, visit www.samhsa.gov or order a copy from
1-800-729-6686.
5 Nora Volkow, et al., Dopamine Transporter Occupancies in the Human Brain Induced by Therapeutic Doses of Oral Methylphenidate, Am J Psychiatry 155:1325-1331, October 1998