Medication - Classes and Effects
Acetaminophen- known by many as "Tylenol". This medication is provided either alone (over the counter), in combination with other OTC drugs like asprin, or in combination with the minor narcotics like hydrocodone (Vicodin/Lorcet) or codeine (Tylenol #3/4). Acetaminophen is unlikely to produce gastric upset or have drug interactions. Unfortunately, this excellent analgesic is particularly toxic to the liver. Patients with liver disease such as hepatitis C and patients who regularly consume alcohol should avoid this medication. Even otherwise healthy individuals should avoid using more than one gram of acetaminophen/day on a regular basis.
NSAIDís (non-steroidal anti-inflammatory drugs)- All members of this class of drugs provide anti-inflammatory relief by inhibiting the production of prostaglandins. The best known of this class is aspirin but also includes other OTC drugs like ibuprofen (Advil/Motrin) and naproxen (Aleve). Many NSAIDS are available only by prescription including Anaprox, Daypro, and many others. All of these drugs can produce gastric upset and damage. Patients with gastrointestinal disorders like acid-reflux disease or ulcer should avoid this class of medication. Patients without GI disorders are cautioned that they might develop such problems with the regular use of this class of drugs. Some NSAIDís are also toxic to the liver. Patients with liver disease should consult closely with their pharmacist before taking these drugs. NSAIDís are primarily prescribed or recommended for musculoskelatal disorders like arthritis but may be use in certain other types of pain.
Novel NSAIDís- This relatively new class of NSAID includes the drugs celecoxib (Celebrex) and rofecoxib (Vioxx), both available at this time by prescription only. These drugs target the COX-2 enzyme and provide anti-inflammatory pain relief. The rate of gastric upset of these drugs is substantially less than traditional NSAIDís but exists nevertheless. Patients with GI disorders should probably not use these medications on any type of regular basis. Recent reports of aseptic (non viral/bacterial) meningitis have caused some concern although the incidence seems rare.
Anti-depressants- The tricyclic anti-depressant amitriptyline (Elavil) has been used in "sub clinical" doses to improve overall pain control in combination with standard analgesics. Tricyclics are an older form of anti-depressant that have a range of side effects from dry mouth to disorientation. Usually, a 10mg dose of Elavil is provided to assist the relief of neuropathic pain. The action of Elavil in this use is not known. More commonly, the SSRIís like sertraline (Zoloft), paroxetine (Paxil), and fluoxitine (Prozac) are prescribed to help reduce the depression and agitation (generalized anxiety) usually associated with chronic pain. The SSRIís are generally well tolerated although sexual dysfunction, sleeplessness, and increased mania can result. The "normal" course of treatment with SSRIís is about six months although some patients with longer term problems may be on this type of medication nearly indefinitely.
Corticosteroids- Steroids are very powerful anti-inflammatories and immunosupressants. They are potentially dangerous drugs that should be used with great caution. Medicines like prednisolone, cortisone, and dexamethasone, are part of this class of drugs which mimic the bodyís own natural steroids produced by the adrenal glands. Steroid drugs can be used topically, orally, by injection, rectally, nasally, in eye or ear applications, or by inhalation. There are many contraindications for these medicines including the presence of ulcer, high blood pressure, infection, and diabetes. These medicines also have a wide range of drug interactions that have to be carefully screened for. Side effects of steroids are multitudinous including weight gain, round face, blue tint to the abdomen, osteoporosis, and adrenal atrophy. While steroids are very useful in the treatment of asthma, allergies, and many other conditions, their primary use in pain control is to reduce inflammation surrounding a joint or spinal process or to treat flare-ups from rheumatoid arthritis or other autoimmune disorders. Even short-term regular use of steroids requires the dose be gradually raised then lowered to minimize steroid withdrawal syndromes.
Anti-convulsants- previously only used for neuropathic pain, many members of this drug class including gabapentin (Neurontin), phenytoin (Dilantin), and carbamazepine (Tegretol) are now being utilized for overall pain management. These drugs act on the brain reducing the overall level of electrical activity. The therapeutic window of this class of drugs can be difficult with serious problems of sedation and even liver damage being produced by too high a dose. Long-term use of this class of medication requires a gradual discontinuation or seizures may result.
"Minor" Narcotics- This class of opiate or opiate like narcotics includes such drugs as codeine (Tylenol #3/4), hydrocodone (Vicodin/Lorcet), and propoxyphene (Darvocette). Usually, these medications are combined with acetaminophen. More rarely, they are compounded with aspirin or even ibuprofen. The acetaminophen or aspirin in these preparations can cause problems with frequent daily doses. Typically, four tablets/day could contain two grams of Tylenol, which is pushing or exceeding the recommended daily dose even for those with healthy livers. Patients using drugs containing acetaminophen should not drink alcohol. Patients should exercise extreme caution in driving a motor vehicle while using these medications.
These are fast acting (20-45 minutes) short half-life drugs (4-6 hours) that provide relief from mild to moderate pain. Tolerance is built quickly (just a few weeks) with ever increasing doses needed. Due to the short duration of the pain relieving effect, pain control over time is difficult with repeated dosing at short intervals required. Minor narcotics used alone for pain control will not work very well for very long. They should not be considered for the management of chronic pain that lasts more than a month or two or where pain episodes occur frequently throughout the week.
"Major" Narcotics- The more powerful or "major" narcotics include morphine, fentanyl, methadone, oxycodone (Percocette), meperidne (Demerol), pentazocine (Talwin) and long acting preparations such as OxyContin (oxycodone time release), MSContin (morphine time release), and fentanyl skin patches (Duragesic). This class of drugs is available by injection, oral doses, tincture, suppositories and skin patches for particularly sustained release. Usually, the major narcotics are reserved for the treatment of severe pain and/or terminal conditions. When needed in chronic pain, the major narcotics, particularly the sustained release forms, are very helpful. Side effects include constipation, sedation, respiratory depression, reduced cognition, and some memory loss. Most of the major narcotics other than oxycodone do not include acetaminophen so liver complications are minimized. In combination with alcohol or other sedatives there exists a real danger of fatal overdose. Patients using the major narcotics should exercise extreme caution in driving or using heavy machinery.
Tolerance to most major narcotics develops quickly with ever increasing doses necessary to achieve adequate pain control. For this reason physicians are likely to consider using methadone because of its particularly long action and slow development of tolerance. Transdermal devices such as Duragesic are also very helpful in providing broad coverage for pain while tending to minimize the tolerance problem. Unfortunately, the skin patches take hours to days to build up adequate blood levels and are quite expensive.
Whenever using narcotics over an extended period of time (weeks to months) it is important to remember that abrupt discontinuation of the medication may result in severe withdrawal symptoms. This can be easily avoided by "ramping" up to the effective dose and "titrating" down when the narcotics are no longer needed. A titration schedule can be provided by the pain specialist and/or pharmacist. Usually, to be safe, titration occurs over weeks or even months to minimize withdrawal. During the titration period it is important to increase other pain relieving methods to compensate where possible for the loss of analgesic effect from the narcotics. Medical cannabis can be particularly helpful to patients who are seeking to reduce or eliminate their narcotic intake.