We conducted a study that assessed 115 patients with refractory chronic migraine over a six year period who were treated with long-acting opiods. This was a select group of patients who had all done well previously with short-acting opiods. 65% of the patients did well for at least nine months (average on the opioid was 4.5 years) and 44% of the patients reported adverse events. Patients with an increased chance of success included young patients, high copers, and those without previous opioid abuse. Predictors of failure were those with personality disorders, older patients, and particularly those with previous abuse of the short-acting opioids. In this study, anxiety, depression, bipolar depression or ADD did not significantly increase the risk of abuse.
Short-acting generally refers not only to how long a drug carries the desired effect, but the speed of the onset of the drug, and how fast it drops off toward the end of the dose. Quick onset and fast dropoff are major determinants for abuse. Short-acting opiods (SAO’s) are not necessarily quick-onset medications. Most oral SAO tablets are slow to take effect. A short duration of action then leads to frequent administration and overuse may occur. However, it has not been proven conclusively that SAO’s lead to less or more abuse, or are “more dangerous” than long-acting opioids (LAO’s). Although certain drugs are more “abusable” it is the person rather than the drug who governs abuse.
Several previous studies have evaluated daily opiods for severe chronic daily headache. While success rates have been relatively low, these are patients who have failed the usual ministrations, with few options available. The advantages of long-acting opioids include:
1. Avoidance of the “end of the dose” phenomenon, with mini-withdrawls throughout the day.
2. Consistent dosing one or two times daily, decreasing the obsession with the next dose.
3. Maintenance of stable blood levels.
4. Avoidance of acetaminophen, aspirin, or NSAIDS that are included in many short-acting preparations.
5. A diminished risk of significant abuse.
6. Better compliance, with less psychological dependency on the drug.
Disadvantages of the long-acting opiods include:
1.stigma
2. fatigue and constipation
3.difficulty in obtaining scripts, with no refills available
4. need for frequent office visits and monitoring
5. risk of abuse
6. interactions with other sedating drugs or alcohol
7. risk of overdose
Most of the opioid abuse is secondary to immediate-acting opioids, or the longer ones that are easily convertible to short-acting ones (ex: Oxycodone CR). Younger people, particularly adolescents, are the most frequent abusers.
Since their introduction in 1982, the LAO’s have not been shown to be widely abused. A balanced approach to prescribing opioids is the best method in order to prevent over or underprescribing opioids. In various studies, the effects of opioids on quality of life are inconsistent. Generally, at least half of the patients prescribed opioids abandon them due to side effects or lack of efficacy.