Hope all is well!
Phonophoresis in Physiotherapy: Mechanism, Physics, Physiology, Indications, Contraindications, Procedure and Research Evidence
Introduction: When Ultrasound Becomes a Drug-Delivery Tool
Imagine a patient sitting in the physiotherapy clinic with painful knee osteoarthritis.
She has already tried exercise, education, activity modification, and other conservative treatments. Today, the physiotherapist applies a small amount of medication-containing gel over the painful region.
Instead of simply rubbing the gel into the skin, the therapist places an ultrasound treatment head over it.
The ultrasound begins to oscillate through the tissues.
The patient asks:
"Is the ultrasound actually helping the medicine get through my skin?"
That question leads us to phonophoresis.
Phonophoresis is the use of ultrasound to enhance transdermal delivery of a topically applied medication or other substance. It is also called sonophoresis in the broader drug-delivery literature.
The idea sounds simple:
Medication on the skin + ultrasound → enhanced transport through the skin
But the science is more complicated.
Ultrasound does not simply "push" a cream deep into the body like a mechanical piston. Several physical processes may contribute, including acoustic streaming, cavitation, changes in skin permeability, thermal effects, and mechanical effects.
And this leads to an important evidence-based question:
Does enhanced drug movement through the skin actually produce better clinical outcomes for patients?
The answer depends on the medication, condition, ultrasound parameters, and comparator treatment.
What Is Phonophoresis?
Phonophoresis is a technique in which therapeutic ultrasound is used to facilitate the movement of a substance across the skin.
The substance is usually incorporated into a suitable coupling medium or topical formulation.
The ultrasound head then delivers acoustic energy through the medication-containing medium and into the skin.
Basic concept
Topical medication → ultrasound energy → altered skin permeability/transport → increased drug movement
The technique has been investigated with substances including:
corticosteroids,
non-steroidal anti-inflammatory drugs,
local anesthetics,
and other topical agents.
However, not every topical medication is suitable for phonophoresis.
The medication's:
molecular size,
chemical structure,
concentration,
solubility,
formulation,
acoustic properties,
and stability
can influence transport.
A Short Story: The Skin's Security Gate
Think of the skin as a building with a very strict security gate.
The outermost layer—the stratum corneum—is the security guard.
Its job is to prevent unwanted substances from entering the body.
A medication sitting on top of the skin therefore faces a significant barrier.
Now imagine ultrasound arriving at that security gate.
Instead of physically forcing the medicine through, the acoustic energy can change the local environment and create conditions that make transport easier.
This is the basic idea behind phonophoresis.
But there is an important lesson:
Making the gate easier to cross does not guarantee that enough medication reaches the final destination to improve the patient's symptoms.
That is why the clinical evidence matters.
Mechanism of Phonophoresis
Several mechanisms have been proposed.
1. Increased skin permeability
Ultrasound can temporarily alter the permeability of the stratum corneum.
This can facilitate movement of some molecules across the skin.
2. Cavitation
Cavitation refers to the formation, oscillation, and movement of microscopic gas bubbles in a fluid exposed to an acoustic field.
These bubbles can alter the local mechanical environment and potentially influence skin permeability.
Cavitation is considered an important mechanism in ultrasound-assisted transdermal drug delivery, although its contribution depends strongly on ultrasound frequency and treatment conditions.
3. Acoustic streaming
Ultrasound produces movement of fluid within the acoustic field.
This phenomenon is called acoustic streaming.
The resulting fluid movement may influence transport of molecules within the topical medium and near the skin surface.
4. Thermal effects
Continuous ultrasound can increase tissue temperature.
Heating can alter:
molecular movement,
blood flow,
tissue extensibility,
and potentially membrane or skin permeability.
However, phonophoresis should not be reduced to "heat pushes medication into tissue."
Thermal and non-thermal mechanisms can coexist.
5. Mechanical effects
Ultrasound produces mechanical pressure oscillations within tissues.
These mechanical effects can influence the skin and surrounding tissues and may contribute to drug transport.
Physics Behind Phonophoresis
To understand phonophoresis properly, we need to understand ultrasound physics.
1. Ultrasound is mechanical energy
Therapeutic ultrasound is a form of mechanical acoustic energy, not electromagnetic radiation.
The treatment head contains a transducer that converts electrical energy into mechanical vibration.
2. Piezoelectric effect
The ultrasound transducer generally uses a piezoelectric material.
When an alternating electrical signal is applied, the piezoelectric crystal changes shape rapidly.
These mechanical changes generate acoustic waves.
Simplified:
Electrical energy → piezoelectric vibration → acoustic wave → tissue
3. Frequency
Common therapeutic ultrasound frequencies include:
1 MHz
3 MHz
The frequency affects how the acoustic energy interacts with tissue and how deeply it can penetrate.
For phonophoresis, however, frequency selection may also influence drug transport.
Experimental human research has compared different frequencies for dexamethasone delivery, demonstrating that frequency can affect the amount of drug detected at different tissue depths.
4. Wavelength
The relationship between frequency, wavelength, and propagation velocity is:
v = f × λ
where:
v = wave velocity
f = frequency
λ = wavelength
Higher frequency generally corresponds to a shorter wavelength within the same medium.
5. Intensity
Ultrasound intensity is commonly expressed as:
W/cm²
Intensity describes the amount of acoustic power delivered per unit area.
Increasing intensity can increase acoustic effects, but higher intensity is not automatically better.
Excessive intensity can increase the risk of unwanted thermal or tissue effects.
6. Duty cycle
Ultrasound can be delivered:
Continuous
The acoustic energy is delivered continuously.
This produces a greater average thermal effect.
Pulsed
The ultrasound is delivered intermittently.
This reduces average energy delivery and generally reduces thermal accumulation.
The appropriate duty cycle depends on the treatment objective and tissue condition.
7. Beam non-uniformity
The ultrasound beam is not perfectly uniform.
There can be regions of:
higher intensity,
lower intensity,
reflection,
interference,
and standing-wave effects.
This is one reason the treatment head should generally be moved according to appropriate clinical technique rather than held motionless over a small area.
8. Coupling medium
Ultrasound does not transmit efficiently through air.
Therefore, a coupling medium is required between the transducer and the skin.
In phonophoresis, the coupling medium can also contain the medication.
The medium needs to permit effective acoustic transmission.
A poorly chosen or poorly applied medium can reduce the efficiency of ultrasound transmission.
Physiology of Phonophoresis
The physiological effects come from both:
the ultrasound itself, and
the medication being delivered.
This distinction is essential.
Ultrasound-related physiological effects
Depending on the parameters, ultrasound may produce:
tissue heating,
altered blood flow,
mechanical effects,
acoustic streaming,
and changes in cellular or tissue behavior.
Medication-related effects
The medication may provide:
anti-inflammatory effects,
analgesic effects,
local anesthetic effects,
or another pharmacological action.
Therefore:
Clinical effect = ultrasound effects + medication effects + rehabilitation context
The relative contribution of each component is not always easy to separate in clinical studies.
How the Phonophoresis Machine Works
A phonophoresis treatment usually uses a conventional therapeutic ultrasound unit.
The machine contains:
Power supply
Electrical oscillator
Ultrasound generator
Piezoelectric transducer
Treatment head
Frequency control
Intensity control
Duty-cycle control
Timer
Coupling medium
The device generates an alternating electrical signal.
The transducer converts this electrical energy into mechanical vibration.
The vibration produces an acoustic field.
That acoustic field travels through the coupling medium and into the patient's tissues.
Simplified pathway
Electrical energy → transducer → acoustic energy → medication-containing coupling medium → skin → tissue
Indications
Phonophoresis is generally considered an adjunctive technique rather than a universal treatment for pain.
Potential applications include:
1. Knee osteoarthritis
Phonophoresis has been investigated as a method for delivering anti-inflammatory or analgesic medications around the knee.
A 2022 systematic review and meta-analysis included nine randomized controlled trials involving 423 patients with knee osteoarthritis. It found significant improvement in pain with NSAID gel phonophoresis and improvement in WOMAC function with corticosteroid gel, although heterogeneity and study limitations remain important.
2. Tendinopathies
Phonophoresis has been investigated for conditions involving painful tendons and peri-tendinous tissues.
However, evidence varies by diagnosis and medication.
It should not be assumed that evidence from one tendon disorder applies to every tendinopathy.
3. Myofascial pain
Phonophoresis has been studied for myofascial pain syndrome.
A randomized study comparing EMLA cream phonophoresis with conventional ultrasound investigated pain, range of motion, and disability in patients with trapezius myofascial pain.
4. Carpal tunnel syndrome
Dexamethasone phonophoresis has been investigated for mild-to-moderate carpal tunnel syndrome.
One randomized study compared dexamethasone phonophoresis with dexamethasone iontophoresis and used 1-MHz ultrasound at 1.0 W/cm² with a pulsed 1:4 cycle.
5. Localized inflammatory or painful soft-tissue conditions
Historically, phonophoresis has been used for localized conditions where a clinician believes topical medication delivery may provide an additional therapeutic effect.
The evidence should be evaluated condition by condition rather than assuming universal effectiveness.
Contraindications
Because phonophoresis combines ultrasound + medication, contraindications for both components must be considered.
1. Medication allergy
The patient must not receive a medication to which they have a known allergy.
2. Medication-specific contraindications
The medication's own contraindications remain relevant.
For example, corticosteroid-related precautions still apply when a corticosteroid is delivered using ultrasound.
Phonophoresis does not make an otherwise inappropriate medication appropriate.
3. Malignancy
Avoid inappropriate ultrasound or medication application over known or suspected malignant tissue unless specifically indicated within an appropriate medical treatment plan.
4. Pregnancy
Treatment should be carefully assessed during pregnancy, particularly over the abdomen, pelvis, or other areas where therapeutic ultrasound may be inappropriate.
5. Active infection
Avoid inappropriate therapeutic ultrasound over an active infection.
6. Active bleeding
Therapeutic ultrasound should be used cautiously or avoided where its effects could aggravate bleeding.
7. Significant vascular disease
Patients with significant vascular impairment require careful assessment.
8. Impaired sensation
Reduced sensation may prevent the patient from recognizing excessive heat or discomfort.
9. Open or severely damaged skin
The treatment area should be appropriate for the ultrasound technique and medication being used.
Medication application over damaged skin can alter absorption and increase risk.
10. Areas where therapeutic ultrasound is inappropriate
Particular caution is required around:
eyes,
testes,
brain tissue,
reproductive organs,
active growth plates in children,
and other anatomically sensitive structures.
Device-specific instructions should always be followed.
Procedure: How Phonophoresis Is Applied
Step 1: Assess the patient
Before treatment, assess:
diagnosis,
pain,
functional limitations,
tissue condition,
skin integrity,
sensation,
medication allergies,
relevant medical history,
and contraindications.
Step 2: Select the medication
The medication must be suitable for the intended treatment.
The clinician should verify:
medication identity,
concentration,
formulation,
compatibility with ultrasound,
patient allergies,
and applicable prescribing requirements.
Not every cream or gel should be used under an ultrasound head.
Step 3: Select ultrasound parameters
Important parameters include:
frequency,
intensity,
duty cycle,
treatment duration,
treatment area,
and coupling medium.
There is no single universal phonophoresis protocol.
Step 4: Apply the medication-containing medium
The medication is applied to the selected treatment area or incorporated into an appropriate coupling formulation.
The formulation should permit adequate acoustic transmission.
Step 5: Position the patient
Position the patient so that:
the treatment area is accessible,
the target tissue is appropriately exposed,
and the patient can remain comfortable.
Step 6: Apply the ultrasound head
The transducer is placed against the coupling medium.
The therapist generally maintains appropriate contact and moves the head according to the treatment technique.
Avoid unnecessarily prolonged stationary application.
Step 7: Start treatment
Begin at an appropriate intensity and duty cycle.
The therapist should monitor:
patient comfort,
skin response,
treatment-head movement,
and tissue response.
Step 8: Continue for the prescribed duration
Treatment duration varies with:
treatment area,
ultrasound parameters,
medication,
clinical goal,
and protocol.
Step 9: Remove the medication and inspect the skin
After treatment:
Remove the ultrasound head.
Clean excess medication as appropriate.
Inspect the skin.
Ask about symptoms.
Document the treatment.
Example Treatment Protocol
There is no universal prescription, but research provides examples.
In a knee osteoarthritis randomized controlled trial, dexamethasone phonophoresis was applied over the medial knee and combined with TENS and quadriceps strengthening exercises. The control group received therapeutic ultrasound plus the same TENS and exercise program. The phonophoresis group demonstrated greater improvement in pain and functional outcomes.
This is an important example because the phonophoresis was not used in isolation.
The broader rehabilitation program still included exercise.
Research Evidence
1. Knee osteoarthritis: systematic review and meta-analysis
A systematic review and meta-analysis examined phonophoresis for knee osteoarthritis.
Nine randomized controlled trials involving 423 participants were included.
The analysis found:
significant improvement in pain with NSAID gel phonophoresis,
improvement in WOMAC function with corticosteroid gel,
but substantial heterogeneity for some outcomes.
For NSAID phonophoresis, pain improvement was statistically significant, but heterogeneity was high.
Clinical interpretation
The findings are encouraging but do not prove that phonophoresis should replace established active management of knee osteoarthritis.
2. NSAID phonophoresis for knee osteoarthritis
Another systematic review and meta-analysis specifically evaluated NSAID phonophoresis.
Eight studies were included, with five contributing to the meta-analysis and 195 participants.
The pooled pain result showed a trend favoring phonophoresis but did not reach a clearly conclusive statistical result. Physical-function outcomes favored phonophoresis.
The authors recommended longer-term studies.
This is a good example of why evidence should not be simplified to:
"Phonophoresis works."
A more accurate interpretation is:
"Some evidence suggests benefit, particularly for certain outcomes, but uncertainty remains."
3. Dexamethasone phonophoresis for knee osteoarthritis
A randomized controlled trial involving 46 women with knee osteoarthritis compared dexamethasone phonophoresis plus TENS and quadriceps strengthening with ultrasound plus TENS and the same exercise program.
Both groups improved.
The phonophoresis group showed greater improvements in pain, Timed Up and Go, WOMAC stiffness, and WOMAC physical function.
Important limitation
The study was relatively small.
Also, because both groups received exercise and TENS, the study demonstrates an additional benefit of the phonophoresis protocol under those conditions—not proof that phonophoresis alone is responsible for all improvement.
4. Neck pain: systematic review
A systematic review examined ultrasound and phonophoresis as additions to exercise or manual therapy for non-specific neck pain.
Six studies involving 249 participants were included.
The evidence quality was rated very low because of:
risk of bias,
inconsistency,
and indirectness.
The review did not provide strong evidence that adding phonophoresis meaningfully improves pain or function beyond active rehabilitation.
Clinical lesson
A modality can have a plausible mechanism and still have weak clinical evidence in a particular condition.
5. Chronic low back pain
A randomized controlled trial involving 60 patients with chronic low back pain compared phonophoresis with ultrasound and control treatment.
The study assessed:
pain,
disability,
trunk muscle strength,
walking,
spinal mobility,
quality of life,
and depression.
This illustrates how phonophoresis has been studied across different musculoskeletal conditions, but evidence should not be generalized from one diagnosis to another.
6. Myofascial pain syndrome
A randomized double-blind placebo-controlled trial involving 60 patients compared phonophoresis, ultrasound, and placebo ultrasound for myofascial pain syndrome.
The study specifically examined whether adding medication delivery through ultrasound provided additional benefit over ultrasound alone.
This type of comparison is especially useful because it asks a clinically meaningful question:
Does the medication add something beyond the ultrasound?
7. Phonophoresis vs ultrasound
A randomized study of 49 people with soft-tissue injuries, including epicondylitis, tendinitis, and tenosynovitis, compared phonophoresis with ultrasound alone.
This type of study is important because it attempts to isolate the additional effect of medication delivery.
8. Does ultrasound actually increase drug penetration?
Experimental evidence supports the possibility of enhanced drug transport.
A human laboratory study investigated dexamethasone penetration using different ultrasound frequencies and measured concentrations at different tissue depths.
This demonstrates that ultrasound frequency can influence drug delivery, but it also shows why dosage cannot be reduced to one simple universal parameter.
The Most Important Evidence Question
Imagine two patients.
Patient A
Receives:
Exercise + education + phonophoresis
Patient B
Receives:
Exercise + education
If Patient A improves more, we have evidence that the additional phonophoresis protocol may have contributed.
But if the study compares:
Phonophoresis + exercise + TENS
with
Ultrasound + exercise + TENS
the interpretation becomes more specific:
Does adding medication to ultrasound provide additional benefit?
This is why clinical trial design matters.
Evidence-Based Practice Analysis
What we know reasonably well
Ultrasound can influence transdermal transport under appropriate experimental conditions.
Physical mechanisms including:
cavitation,
acoustic streaming,
mechanical effects,
and thermal effects
can alter permeability and drug movement.
What remains uncertain
The major uncertainty is whether the amount of medication delivered produces a sufficiently large clinical effect.
Drug penetration is not the same as:
pain relief,
functional improvement,
faster tissue healing,
or long-term recovery.
Phonophoresis Is Not Simply "Ultrasound With Cream"
This is an important clinical distinction.
If a therapist applies ordinary ultrasound gel containing no active medication, that is simply therapeutic ultrasound.
For phonophoresis, there must be an intentional attempt to use ultrasound to facilitate transport of an appropriate substance.
The medication formulation therefore matters.
Advantages of Phonophoresis
1. Non-invasive drug delivery
It avoids a needle.
2. Local application
Medication can be targeted toward a symptomatic region.
3. Combines two therapeutic concepts
The treatment incorporates:
ultrasound,
and pharmacological delivery.
4. Potentially useful for patients who cannot tolerate injections
It may provide another option in selected situations.
5. Can be combined with exercise
This is often the most clinically useful way to incorporate the modality.
Limitations
1. Drug penetration is variable
Not every drug crosses the skin equally well.
2. Clinical evidence is condition-specific
Evidence for knee osteoarthritis cannot automatically be transferred to neck pain, tendinopathy, or carpal tunnel syndrome.
3. Protocols vary
Studies differ in:
ultrasound frequency,
intensity,
duty cycle,
duration,
medication,
concentration,
and treatment schedule.
4. Long-term evidence is limited
Several studies focus primarily on short-term outcomes.
5. Medication risks remain
Phonophoresis does not remove the adverse effects or contraindications of the medication.
Common Clinical Mistakes
Mistake 1: Using any cream as phonophoresis medication
Not every cream is appropriate.
The formulation must be compatible with the ultrasound and intended delivery mechanism.
Mistake 2: Assuming deeper penetration always means better treatment
More drug penetration is not automatically equivalent to better clinical outcomes.
Mistake 3: Using excessive ultrasound intensity
Higher intensity does not automatically produce better drug delivery.
It may instead increase unwanted tissue effects.
Mistake 4: Holding the treatment head stationary
This can increase local energy deposition and create unnecessary risk.
Mistake 5: Ignoring medication contraindications
The ultrasound machine does not make medication risk disappear.
Mistake 6: Using phonophoresis instead of rehabilitation
For most chronic musculoskeletal conditions, passive treatment should not replace appropriate active rehabilitation.
Story Example: From the Treatment Table to the Gym
Let's return to our patient with knee osteoarthritis.
She arrives with pain when climbing stairs.
The physiotherapist performs an assessment and identifies quadriceps weakness, reduced activity tolerance, and pain during loading.
Instead of saying:
"We will treat your knee with ultrasound."
the clinician develops a broader plan:
Education → progressive quadriceps strengthening → functional loading → activity modification → symptom management
Phonophoresis may be added if there is a specific rationale for topical medication delivery.
The ultrasound treatment may help with short-term symptoms.
But the real rehabilitation goal is not simply:
"Make the pain disappear during today's appointment."
The goal is:
"Help this person climb stairs, walk, exercise, and live with greater confidence and function."
That distinction is what separates a modality-centered approach from a patient-centered rehabilitation approach.
Myths and Facts
Myth: Phonophoresis forces medicine deep into the muscle.
Fact: Ultrasound can enhance transdermal transport, but penetration depends on the medication, formulation, acoustic parameters, skin properties, and treatment conditions.
Myth: More ultrasound intensity means more medication.
Fact: Drug delivery is not linearly related to intensity in a simple way.
Myth: Phonophoresis is always better than ultrasound.
Fact: Some studies show additional benefit, while other research finds little or uncertain added benefit.
Myth: Phonophoresis cures arthritis.
Fact: It may help symptoms in selected patients, but it does not reverse the structural changes of osteoarthritis.
Myth: Phonophoresis is completely risk-free.
Fact: Both ultrasound and the medication have contraindications and precautions.
Myth: If the medication penetrates the skin, the treatment has succeeded.
Fact: Successful transdermal delivery is a biological outcome; successful rehabilitation requires meaningful improvement in symptoms, function, or participation.
Frequently Asked Questions
Is phonophoresis the same as iontophoresis?
No.
Phonophoresis: uses ultrasound to facilitate drug transport.
Iontophoresis: uses electrical current to facilitate transport of charged substances.
What medications are commonly used?
Research has investigated corticosteroids, NSAIDs, local anesthetics, and other substances.
The medication must be appropriate for the intended application and compatible with the phonophoresis technique.
Does phonophoresis hurt?
Usually, patients should not experience significant pain from the ultrasound itself.
Some patients may experience mild warmth or other sensations depending on the parameters.
How long does a phonophoresis treatment take?
Treatment duration depends on:
treatment area,
ultrasound parameters,
medication,
clinical objective,
and the treatment protocol.
There is no universal duration.
Can phonophoresis be used every day?
Frequency should be determined by the clinical condition, ultrasound dose, medication, skin response, and overall treatment plan.
More frequent treatment is not automatically better.
Is phonophoresis better than an injection?
The two techniques are fundamentally different.
An injection delivers medication directly through a needle, while phonophoresis attempts to facilitate transdermal delivery.
Clinical outcomes depend on the condition and medication.
Can phonophoresis replace exercise?
No.
For most musculoskeletal rehabilitation, exercise and functional rehabilitation remain important components.
Phonophoresis may be used as an adjunct when there is a specific rationale.
Evidence-Based Takeaway
Phonophoresis combines therapeutic ultrasound with transdermal drug delivery.
Its theoretical pathway is:
Ultrasound → mechanical/thermal effects → altered skin permeability → enhanced medication transport → potential local pharmacological effect
The physical mechanism is plausible and supported by experimental research.
Clinical evidence is more variable.
For knee osteoarthritis, systematic reviews and randomized trials suggest that some phonophoresis protocols can improve pain and certain functional outcomes, although heterogeneity and limitations remain.
For non-specific neck pain, evidence supporting additional benefit from phonophoresis is much weaker, with one systematic review rating the evidence very low quality.
Therefore, the appropriate clinical question is not:
"Does phonophoresis work?"
A better question is:
"For this patient, with this diagnosis, this medication, and this treatment goal, does adding phonophoresis provide a meaningful benefit beyond appropriate rehabilitation?"
That is the evidence-based question.
Conclusion
Phonophoresis is an interesting bridge between physical therapy, ultrasound physics, skin physiology, and pharmacology.
The technique attempts to use acoustic energy to improve the movement of a topical substance through the skin.
Its mechanisms may involve:
cavitation,
acoustic streaming,
mechanical effects,
thermal effects,
and changes in skin permeability.
But understanding the mechanism is only the beginning.
A physiotherapist must also consider:
the medication,
its formulation,
ultrasound frequency,
intensity,
duty cycle,
treatment duration,
skin condition,
patient-specific contraindications,
and the evidence for the particular diagnosis.
The best use of phonophoresis is therefore not to treat the ultrasound machine as the "main treatment."
Instead:
Use the modality when there is a clear rationale, monitor the patient carefully, and connect the treatment to an active rehabilitation plan and meaningful functional goals.
In the end, the success of phonophoresis is not measured by how smoothly the ultrasound head moves across the skin.
It is measured by whether the patient can eventually do something that mattered to them—walk more comfortably, climb the stairs, return to exercise, work, or simply move through daily life with less limitation.
Selected References
Byl NN. The use of ultrasound as an enhancer for transcutaneous drug delivery: phonophoresis. Physical Therapy. PMID: 7770499.
Williams AR. Drug delivery by phonophoresis. PMID: 2664754.
Azagury A et al. Ultrasound-mediated transdermal drug delivery: mechanisms, scope, and emerging trends. PMID: 21238514.
Martin-Vega FJ et al. Phonophoresis through nonsteroidal anti-inflammatory drugs for knee osteoarthritis treatment: systematic review and meta-analysis. PMID: 36552010.
Systematic review and meta-analysis of phonophoresis for knee osteoarthritis. PMID: 35896559.
Ahmed MAS et al. Improved pain and function in knee osteoarthritis with dexamethasone phonophoresis: randomized controlled trial. PMID: 31673169.
Dorji K et al. Effect of ultrasound or phonophoresis as an adjuvant treatment for non-specific neck pain: systematic review of randomized controlled trials. PMID: 33253599.
Bakhtiary AH et al. Phonophoresis of dexamethasone sodium phosphate in patients with carpal tunnel syndrome. PMID: 23042475.
Ustun N et al. Efficacy of EMLA cream phonophoresis compared with ultrasound therapy in myofascial pain syndrome. PMID: 24149990.
Ay S et al. Comparison of the efficacy of phonophoresis and ultrasound therapy in myofascial pain syndrome. PMID: 20354859.
Durmus D et al. Is phonophoresis effective in the treatment of chronic low back pain? PMID: 23283539.
Dexamethasone sodium phosphate penetration during phonophoresis at two ultrasound frequencies. PMID: 32320285.
Effects of therapeutic ultrasound for knee osteoarthritis: systematic review and meta-analysis. PMID: 31382781.
Clinical note: Phonophoresis involves both an ultrasound modality and a medication. Medication selection, formulation, prescribing requirements, contraindications, ultrasound parameters, and device instructions should be verified according to the patient's clinical situation and applicable professional regulations.
