Many conditions may be treated with injection therapy, including:

• Pain in and around the spine (e.g., back, neck, hip). This may be due to a number of causes, including skeletal disorders, disc disease or painful knots of muscle. However, in more than 80 percent of cases of chronic back pain, there is no clearly identifiable etiology (cause).
  
  
• Bursitis. Inflammation of a bursa, a fluid-filled pad located throughout the body that lubricates areas where tendons and muscles pass over bony projections. It can occur in a number of areas of the body, including the shoulder, elbow, hip, knee and ankle.
  
  
• Carpal tunnel syndrome. Wrist condition resulting in numbness, weakness and other symptoms in the hand and fingers. Carpal tunnel syndrome is due to compression of the median nerve in the wrist, according to the National Institutes of Health. However, many patients have surgery to relieve the compression but don't have a reduction in symptoms, and there are people who have identifiable compression of the nerve without any symptoms.

• Neuralgia. Pain resulting from injury to the nerves. The area of the body affected depends on the specific nerve pathway affected.  Types of neuralgia include postherpetic neuralgia, which results from shingles and usually affects the trunk or the face and scalp, and cranial neuralgias such as trigeminal neuralgia. Patients may experience sensations that include pins and needles, shock-like episodes, sharp stabbing pain or a constant burning pain.
  
  
• Osteoarthritis. Arthritis caused by wear to joints. Common areas affected include the hands, hips, knees, neck and lower back.

• Rheumatoid arthritis. Inflammatory disorder in which the immune system attacks the body.
  
  
• Sciatica. Pain that radiates along the longest nerve in the body (the sciatic nerve). This nerve runs from the pelvis through the buttocks and hip area and down the back of each leg. Pain is usually the result of pressure on the nerve.
  
  
• Shingles. Condition that affects nerves in the skin, causing a painful rash in people who previously have had chickenpox or the chickenpox vaccine.
  
  
• Tendinitis. Inflammation or irritation of a tendon due to overuse. It commonly affects the shoulders, knees, elbows and hips.
  
  
• Tennis elbow (lateral epicondylitis). Inflammation or pain on the outside of the upper arm near the elbow.

• Golfer elbow (medial epicondylitis). Inflammation or pain along the inner elbow.
  
  
• Cancer pain. Cancer patients may receive opioid injections for pain. Pain caused by pancreatic cancer may be treated with celiac plexus blocks.
  
  
• Cervical dystonia. A painful nerve disorder that causes severe contractions of neck and shoulder muscles. The U.S. Food and Drug Administration (FDA) has approved injections of neurotoxins called botulinum toxin type A (Botox) and botulinum toxin type B (Myobloc) to treat cervical dystonia.

The FDA has also approved Botox injections to treat two eye muscle disorders (blepharospasm and strabismus) and severe underarm sweating (primary axillary hyperhidrosis). Scientists are studying Botox as a potential treatment for many other conditions, including migraines, osteoarthritis, writer's cramp, back pain and prostate enlargement (benign prostatic hyperplasia).