There are several categories of pain medications physicians prescribe to manage both acute and chronic pain. The choice of medication depends on the severity of pain, source of pain, whether it is recurring and concomitant health problems of the patient.
Acetaminophen
This over-the-counter pain medication is widely used and is commonly recommended or prescribed by physicians to treat mild to moderate pain. Most people know this medication by the brand name Tylenol. It reduces pain as well as fevers. It is also not addictive. Furthermore, its side-effect profile is favorable within a certain dose range. The maximum dose is 4,000mg per day in an adult. However, doses above the recommended range can result in severe liver toxicity, which can be fatal. It is a component in many medication combinations such as cold medications and other painkillers, so patients should be aware of the amount of acetaminophen they take from all medications cumulatively.
Nonsteroidal Anti-Inflammatory Drugs
This category of medications includes commonly known ibuprofen and naproxen. NSAIDs are effective in mild to moderate pain and fever reduction, as with acetaminophen. Unlike acetaminophen, they also are anti-inflammatory. This can help in a variety of conditions from inflammatory arthritis to minor injuries. The side effects of NSAIDs can limit their use. They can cause gastrointestinal side effects such as stomach pain and ulcers. Many NSAIDs inhibit platelet function, and generally are avoided in patients on blood-thinners or with bleeding problems. They can cause various types of kidney injury, and should be used with caution or avoided in patients with kidney disease. A subset of NSAIDs, called COX-2 inhibitors, do not have the platelet-inhibiting properties and may have fewer gastrointestinal side effects in the short term. Other side effects include allergies, neurological side effects and liver injury. NSAIDs are available over the counter and are also prescribed in higher doses.
Tramadol
This unique medication has a profile that acts like a weak opiate, although it does have effects on serotonin and norepinephrine, which may contribute to pain relief. It is only available by prescription. Its side effect profile is similar to opiates. It also increases the risk of seizures.
Opiates
This category of medication includes the commonly known morphine. Opiates are medications typically reserved for severe acute pain. Some patients with chronic pain also take opiates, but the risks must be weighed carefully when used in these cases. They work on pain receptors in the central nervous system, making them very effective in pain relief. Side effects include sleepiness, constipation, low respiratory and heart rate, euphoria and dependence. These are available by prescription only and should be given by one physician at a time to monitor use.
Tricyclic Antidepressants
These include medications such as amitriptyline and nortriptyline. While they are antidepressants, they are often used for pain relief in the presence or absence of depression. The mechanism of pain relief is unclear, but it is thought to be associated with effects on serotonin and norepinephrine. They are often used in patients with chronic pain. Side effects include sleepiness, constipation, dry mouth, mental clouding and heart conduction disturbances.
Anticonvulsants
These medications are indicated to treat seizures but can also help patients with chronic pain, particularly from a nerve problem such as peripheral neuropathy. Some common side effects include sleepiness, dizziness and fatigue. Rarely, they can cause blood count abnormalities, skin reactions and kidney injury.
