Osteoarthritis Medicines
Osteoarthritis can be managed but till date, it is incurable with medications. The symptoms can be alleviated with medications which control the underlying pathology. These can help provide the patient with a better quality of life by improving functionality and increasing vitality of the joints affected by OA. The two broad groups of medicines used for OA are:
Analgesics
Analgesics are painkillers. They form the first line of treatment because the pain in joints is primarily the presenting complaint in such patients. Acetaminophen is the most commonly used agent in this class. It also has effects like reducing inflammation and fever.
Acetaminophen, (paracetamol or Tylenol) is an inhibitor of the mediators of pain. With the inhibition of the pathway, the symptoms of the patient are relieved, allowing mobility of the joint and enabling the patient to perform tasks which were previously limited by pain of osteoarthritis. This inhibition of the inflammatory mediators does not occur at other sites like gastrointestinal tract. This causes limitation of side effects of this drug. It is an FDA approved drug which is available as over the counter medicine in various formulations like oral pills, injectable and syrups etc. Possible but rare side effects of acetaminophen are due to overdose of the drug. Otherwise the drug is well tolerated, with no significant allergic reactions. Some side effects are:
- Fall in blood sugar
- Kidney damage
- Thrombocytopenia
- Liver damage.
Opioids
The progressively worsening osteoarthritis escalated pain to such a level that it escapes the analgesic effect of acetaminophen. In such cases, combined preparation of acetaminophen with opioids is used. These drugs are narcotic and addictive and have to be closely monitored in terms of dose and frequency. New research has identified a chondrotoxic role of opioids but they are still prepared for pain relief purpose. The potential side effects include:
- Potential for abuse
- Addiction
- Constipation
- Increased sleep
Topical agents
These medications are gels or oils that are directly applied over the aching joints in order to relieve pain. These are a choice for patients who cannot tolerate the side effects of drugs like NSAIDs. The active agent in these preparations is either capsaicin which is also found in red peppers, or methyl salicylate. Diclofenac is an NSAID that can be used topically and is manufactured in the gel preparations.
NSAIDs
Now let’s come to the most popular drugs for OA, the non-steroidal anti-inflammatory drugs. As the name shows these have an anti-inflammatory role. These control the inflammation in joints and surrounding tendons and bursa, which could be damaged due to the progressive bone deformity. They also inhibit the mediators of inflammation by inhibiting the enzymes COX-1 and COX-2. However, COX- 2 is not only found in bones and joints, but in other parts of the body too, where its inhibition leads to some very important side effects like:
- GI symptoms like stomach pain, leading to erosion and ulcers.
- Nausea and diarrhea
- Headache
- Dizziness
- Allergy to aspirin in some patients
However, NSAIDs used according to the doctor’s prescription is the best available treatment option.