Acupuncture most commonly refers to a method of inserting thin, sterile, solid needles into specific sites on the body that, when activated, induce complex, autoregulatory physiologic responses within the central, peripheral, and autonomic nervous systems. Aside from needling, however, acupuncture may incorporate an array of interventions intended to either augment the needle’s effects or obviate the need for needling altogether. Such interventions include:
- electrical stimulation (electroacupuncture) 
- moxibustion, in which a smoldering herb heats an acupuncture point or embedded needle 
- laser stimulation (laser acupuncture) 
- pressing techniques (acupressure) 
- injection of fluids with substances such as vitamins, saline, herbs, homeopathics, or medications into acupuncture point locations; this technique is termed aquapuncture or, when referring to medication injections, pharmacopuncture 
Of these, electroacupuncture most frequently appears in scientific studies because of its robust and reliable physiologic influences.
The scientific approach to acupuncture, often referred to as medical acupuncture, evolved from Asian acupuncture decades ago. It regards acupuncture as part of conventional medicine, not something "alternative." Medical acupuncturists use current knowledge of anatomy, physiology, pathology, and neuromodulation to explain the mechanisms of action instead of relying on metaphorical concepts such as Yin, Yang, and Chi (or mystical energy). Modern medical insights have elucidated, in detail, the many ways acupuncture works. This includes neurophysiologic changes in the central, peripheral, and autonomic nervous systems, as well as connective tissue influences that serve to normalize tension and circulation within and throughout the myofascial network.
Mechanisms of Action of Acupuncture in Veterinary Patients
Acupuncture is a comparatively widely utilized complementary therapy. It is based on traditional Chinese medicine and involves insertion of thin needles into specific points on the body. Such point stimulation is believed to activate somatic afferent nerve fibers in the nearby tissue. By adopting a gentle treatment technique, an acupuncturist selectively stimulates mechanoreceptors rather than nociceptors, aimed at augmenting endogenous analgesic mechanisms. Signals traveling along these neural pathways initiate a series of reflexive and homeostatic responses within the local, regional, autonomic, and central nervous systems. Acupuncture is thus thought to result in benefits including alleviation of pain, inflammation and improved local circulation. Furthermore, neuromodulation may affect neurotransmitter concentrations and overall CNS function, potentially benefiting the patient.
Ultimately, the specific improvements that may occur in response to acupuncture depend on the skill of the medical acupuncturist;, the patient's health status and disease chronicity; and the locations and types of stimulation selected for treatment. If performed correctly, acupuncture treatment is generally regarded as safe; however, depending on the species caution should be exercised and appropriate training is always indicated.
Indications for Acupuncture in Veterinary Patients
Research into medical acupuncture presents challenges and the level of evidence in support of efficacy varies. Nonetheless, acupuncture is often part of integrative veterinary medicine. Indications for which veterinarians may prescribe for acupuncture include signs of pain, weakness, neurologic injury or disease, immune dysfunction, digestive disorders, reproductive disturbances, and more. Suggested Indications and Approaches for Acupuncture in Veterinary Patients lists conditions typically encountered in a veterinary medical acupuncture practice. The table also presents typical neuromodulatory goals and myofascial considerations that inform and direct a science-based acupuncture intervention.
Suggested Indications and Approaches for Acupuncture in Veterinary Patients
| Condition | Treatment Goals | Central or Peripheral Nervous System Points or Regions Treated | Autonomic Nervous System Points and Purported Rationale | Myofascial Component, Assessment, and Treatment Goals | 
|---|---|---|---|---|
| Abdominal pain | Analgesia 
 | Paraspinal points to neuromodulate spinal cord segments that associate with dysfunctional viscus or viscera (BL17-–BL25) | Fibular nerve point (ST36) for parasympathomimetic, anti-inflammatory, and analgesic effects. Consider PC6 for cranial abdominal discomfort and nausea. | Relax truncal tension stemming from and/or contributing to abdominal discomfort. Palpate for and treat myofascial restriction and dysfunction, and needle or otherwise address tissue tension. | 
| Back and neck pain | Identify, characterize, and localize the nature of back or neck pain through observation of movement, palpation, and posture when sitting and standing. | Paraspinal and selective dorsal midline points related to back pain. GV, inner BL line, outer BL line, Huatuojiaji points at relevant and adjacent spinal cord segments. | Sympathetic neuromodulation by means of paraspinal points with resultant anti-inflammatory effects through presumptive lowering of sympathetic tone. Reinforce with popliteal neurovascular point (BL40) and/or ST36. | Relax back, neck, and paraspinal tension as discerned by means of myofascial palpation. This reduces pain and improves range of motion. Needle or otherwise address tissue tension and shortening. | 
| Joint pain | Analgesia 
 Improved Function 
 | Select paraspinal points related to spinal cord segments that supply peripheral nerves innervating targeted arthrodial and peri-articular structures to neuromodulate "facilitated" or "wound up" spinal cord segments. | Points at neurovascular locations near and/or distal to the targeted joint(s). For example, ST36, BL40, and LR3 for pelvic limb pain, and LI11, LU7, and LI4 for thoracic limb pain to reduce overactive sympathetic tone. | Palpate for sources of local, regional, and referred pain. Relax tissue, improve range of motion, decompress nerves and vessels affected by myofascial restriction. | 
| Postoperative ileus | Restore proper GI motility Provide analgesia to area affected by surgery to remove additive effects on ileus from overactivation of the sympathetic nervous system. | Paraspinal points to neuromodulate spinal cord segments that associate with involved viscus or viscera (BL17-BL25) | Fibular nerve point (ST36) for parasympathomimetic, anti-inflammatory, and analgesic effects. Consider PC6 for motility disorders involving the esophagus and/or stomach. | Relax truncal tension stemming from and/or contributing to digestive dysfunction. Palpate for and treat myofascial restriction and dysfunction, and needle or otherwise address tissue tension. Address soft-tissue pain related to surgery and/or anesthesia. | 
| Facial nerve injury | Restore function to injured components of the somatic motor fibers of the facial nerve. | Stimulate peripheral/cranial nerve branches from the point of exit from the cranium to the neuromuscular endpoint. | Improve circulation to the face and, in particular, the injured neural tissue, either through local trigeminal nerve activation or through CNS modulation of vascular tone. | Release soft-tissue restrictions impacting involved neural pathways. Activate somatic motor tissue on the head through sensory inputs that restore neural control over muscles of facial expression. | 
| Peripheral nerve injury | Facilitate repair of injured nerve. Remove soft-tissue restrictions that cause neurologic dysfunction by means of neural compression. Improve local circulation to optimize tissue repair. | Activate spinal nerves related to spinal cord origins of involved peripheral nerve(s). Continue treatment along respective axons (that often follow one or more acupuncture channels on a limb). | Normalize circulation through autonomic neuromodulation of vascular tone. | Relax soft-tissue restrictions that are perpetuating neural dysfunction. Activate sensory and motor pathways associated with the injured nerve(s) to expedite return to function. | 
| Spinal cord injury | Neuromodulate/normalize firing patterns in the spinal cord and affected nerves. Protect existing tissues from further decline. Encourage restoration of function of sensory, motor, and autonomic pathways, including control of urination and defecation. | Stimulate spinal nerves related to spinal cord origins of involved peripheral nerve(s). Continue treatment along respective axons (that often follow one or more acupuncture channels on a limb). | Restore healthful circulation through autonomic neuromodulation of vascular tone in the spinal cord through medical acupuncture and related techniques directed to the injured cord levels as well as three segments proximal and distal to the lesion. This takes into account neural divergence by afferent input across multiple levels. | Palpate for sources of local, regional, and referred pain. Relax tissue, improve range of motion, and decompress nerves and vessels affected by myofascial restriction. | 
| Urinary/fecal incontinence | Neuromodulate spinal cord segments and reflex pathway nerves that encourage restoration of voluntary control of urination and defecation. | Stimulate spinal nerves related to CNS components involved in micturition and defecation, ranging from the thoracolumbar to sacral cord segments. Amplify and reinforce the influence of distal peripheral nerves on these reflex systems with acupuncture points such as KI3 and SP6, both strong influencers of the tibial nerve and its role in neuromodulation of genitourinary function. | Normalize reflexive control over micturition and defecation in the brain and spinal cord (thoracolumbar through sacral spinal cord segments and affiliated spinal nerves). Suggested points include BL points from BL19-BL25 and locations over the sacrum to influence dorsal spinal nerves (ie, BL27-BL30). | Palpate for sources of local, regional, and referred pain and aberrant stimuli that are impacting mechanoreceptor control over voiding. | 
| Nonhealing wound | Provide anti-inflammatory, anti-infective, and immune-enhancing support to local tissues through optimization of host defenses and normalization of regional blood and lymph flow. | Improve host health and proper circulation and immune surveillance through neuromodulation of CNS tone that reduces wind-up and stress within the system in general. Acupuncture points that aid in this approach include paraspinal (BL channel) points associated with spinal cord segments that supply the wound. | Improve host health and proper circulation and immune surveillance through neuromodulation of autonomic nervous system tone. This involves, to a great extent, reducing overactive sympathetic drive. Points suggested include LI4 and LI11 on the thoracic limb and LR3 and ST36 on the pelvic limb. | Surround nonhealing wound by needling or otherwise activating resident fibroblasts in the local tissue. Adjunct methods include photonic stimulation (eg, laser therapy or light-emitting diodes [LEDs] and/or stretch via massage). Acupuncturists may refer to this approach as "circling the dragon [the wound]". | 
| Immunologic dysfunction | Instill immune-balancing input to the individual as a whole. | Improve host health and proper circulation and immune surveillance through neuromodulation of CNS tone that reduces wind-up and stress. Acupuncture points that may assist in this manner include GV20, GV14, GV4, BL18, and BL23. | Improve host health and proper circulation and immune surveillance through neuromodulation of autonomic nervous system tone. This involves, to a great extent, reducing overactive sympathetic drive. Acupuncture points that may assist in this manner include LI4, ST36, SP6, and BaiHui at the lumbosacral junction. | Remove nociceptive aggravation borne by soft-tissue dysfunction by relaxing the patient's soft tissues and nervous system through comforting, pain-alleviating interventions. | 
Contraindications for Acupuncture in Veterinary Patients
- Whereas acupuncture is generally regarded as safe, it may be contraindicated if a veterinary patient cannot remain still enough to perform needling safely. High levels of anxiety, fear, or aggression could counteract health-promoting autonomic changes generated by acupuncture. In such cases, efforts to calm the animal may be warranted, or the procedure should not be performed. 
- Although pregnancy is often considered a contraindication due to concern that acupuncture might affect hormone levels or uterine innervation, evidence of serious adverse effects is lacking, even in late pregnancy. 
- Coagulopathies or immune compromise might represent contraindications if needling leads to excessive bleeding or local infection, respectively. 
- In animals with cancer, caution should be exercised to avoid areas of neoplasia or tumor. Similarly, needling infected regions of the body surface should be avoided. 
Adverse Effects of Acupuncture in Veterinary Patients
Acupuncture provided by appropriately trained veterinary professionals generally results in few adverse effects. The risks of iatrogenic injury to a major organ or vessel with a needle are reportedly limited provided the practitioner is cognizant of relevant anatomic landmarks. Extreme negative reactions may indicate that the needle has entered a nerve; in those cases, the needle should be immediately withdrawn. It should be noted that horses may react badly and injure practitioners and handlers during acupuncture treatment. Needle ingestion by the patient is possible, although there are no published reports of injury. Adverse reactions in people include syncope, skin infections, and hepatitis; such reactions have apparently not been reported in veterinary patients.
