Voltaren vs Ketro RX Pain Gel: OTC Diclofenac vs Prescription Ketorolac
Targeted Pain Relief. Applied Where It Hurts, Not Swallowed.
Ketro RX Pain Gel uses ketorolac, a prescription NSAID that StatPearls describes as having higher demonstrated potency than most other NSAIDs. Voltaren's active ingredient, diclofenac 1%, is an OTC NSAID. Both are topical, but Ketro RX is compounded per patient under physician oversight while Voltaren is sold at a fixed OTC concentration.
Voltaren (diclofenac 1% gel) became the first topical NSAID approved for over-the-counter sale in the US, in February 2020, and is widely available over the counter. But OTC means fixed strength, limited potency, and a one-size-fits-all formulation. For people whose pain needs more than what you can buy off the shelf, prescription-strength ketorolac offers a fundamentally different level of anti-inflammatory power.
This page compares the two products head-to-head: active ingredients, potency, clinical evidence, cost, and when to choose which. No marketing spin. Just the pharmacology.
Rx
Prescription-strength ketorolac, compounded per patient
1%
Voltaren's fixed OTC diclofenac concentration
8,000+
Participants in Cochrane topical NSAID evidence base
Last updated April 16, 2026
Key Takeaways
- 1. Both Ketro RX and Voltaren are topical NSAIDs that deliver medication through the skin, but Ketro RX uses prescription-strength ketorolac, traditionally reserved for hospital and emergency department use, while Voltaren is OTC diclofenac at a fixed 1% concentration.
- 2. Voltaren is OTC, affordable ($15-25), and effective for mild to moderate pain. Ketro RX requires a prescription and starts at $110/month, about $3.67 a day with the physician consultation included, but provides higher potency for pain that OTC can't manage.
- 3. Topical diclofenac 1% gel produced 5-17x lower systemic exposure than oral diclofenac in healthy volunteers (Kienzler 2010, DOI 10.1177/0091270009336234). In osteoarthritis trials, topical NSAIDs as a class showed no significant difference from placebo for GI events, though they showed more withdrawals for adverse events overall, mostly skin reactions. Lower systemic exposure, not zero.
- 4. The right choice depends on pain severity: mild/occasional pain may respond well to Voltaren, while moderate-to-severe or chronic inflammatory pain may benefit from prescription-strength ketorolac.
Ready to see if prescription-strength topical ketorolac is right for your pain? Start a free online consultation and a licensed physician will review your case within 24 hours.
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Voltaren vs Ketro RX: Side-by-Side Comparison
| Feature | Ketro RX Pain Gel | Voltaren (Diclofenac) |
|---|---|---|
| Active Ingredient | Ketorolac (prescription NSAID) | Diclofenac sodium 1% |
| Strength | Prescription-strength, compounded per patient | Fixed OTC concentration (1%) |
| Availability | Prescription required (online consultation included) | Over-the-counter at any pharmacy |
| Analgesic Class | Prescription-strength NSAID, traditionally reserved for hospital and ED use | OTC NSAID, broadly used for mild-to-moderate pain |
| Anti-inflammatory Action | Topical NSAID with comparable anti-inflammatory effect to other topical NSAIDs | Topical NSAID at fixed 1% diclofenac |
| GI Side Effects | In osteoarthritis trials, topical NSAIDs as a class showed no significant difference from placebo for GI events (OR 0.96). Ketorolac was not among the drugs pooled | In osteoarthritis trials, topical NSAIDs as a class showed no significant difference from placebo for GI events (OR 0.96). Topical diclofenac was among the drugs pooled |
| Application | Apply to affected area as directed by physician | Apply up to 4x daily per package directions |
| Cost | From $110/month (online consultation included) | ~$15-25 OTC |
| Origin | Originally developed by the same compounding team that works with professional sports organizations, including the Boston Red Sox | Novartis / GSK consumer health |
| Compounding | Made per patient by US pharmacy (Precision Compounding) | Mass-manufactured, fixed formula |
Ketorolac vs Diclofenac: The Two NSAIDs Behind the Products
Ketorolac and diclofenac are both NSAIDs that work by inhibiting COX enzymes. Diclofenac 1% gel is the only OTC topical NSAID available in the US, sold as Voltaren and as store brands. Ketorolac is available by prescription only, in oral, nasal spray, IV and IM forms, and the topical ketorolac in Ketro RX Pain Gel is compounded per patient.
| Feature | Diclofenac (Voltaren) | Ketorolac (Toradol) |
|---|---|---|
| Drug class | NSAID. Inhibits cyclooxygenase (COX) enzymes | NSAID. Inhibits cyclooxygenase (COX) enzymes |
| Brand names | Voltaren in the US, Voltarol in the UK. Store brands and other labels sell the same 1% gel, including Aspercreme Arthritis Pain | Toradol, listed by MedlinePlus as a discontinued US brand. Generic ketorolac is still available |
| US prescription status | Both. Diclofenac 1% gel is the only OTC topical NSAID available in the US, and diclofenac topicals also carry prescription labels | Prescription only |
| FDA-approved dose forms | Oral tablets, topical gel, topical solution | Oral, nasal spray, IV, IM (StatPearls) |
| What the OTC label covers | "Temporary relief of arthritis pain ONLY in the following areas: hand, wrist, elbow (upper body areas) foot, ankle, knee (lower body areas)". The label adds: "Do not use...for strains, sprains, bruises or sports injuries" | No OTC form exists |
| What the prescription label covers | Diclofenac sodium topical gel 1%: "relief of the pain of osteoarthritis of joints amenable to topical treatment, such as the knees and those of the hands" | Ketorolac tablets: "short-term (5 days or less) management of moderately severe acute pain that requires analgesia at the opioid level, usually in a postoperative setting" |
| Duration limit on the label | OTC Voltaren: "use up to 21 days unless directed by your doctor" | Systemic ketorolac: combined IV, IM and oral use "not to exceed 5 days" |
| Application frequency | OTC label: 4 times per day, on no more than 2 body areas at the same time | Set by the prescribing provider |
| Boxed warning on the prescription label | "WARNING: RISK OF SERIOUS CARDIOVASCULAR AND GASTROINTESTINAL EVENTS" | Four boxed warnings: gastrointestinal, cardiovascular thrombosis, renal, bleeding |
| Topical head-to-head trial | None published against ketorolac | None published against diclofenac |
Is Toradol the Same as Voltaren?
No. Toradol is a brand name for ketorolac and Voltaren is a brand name for diclofenac, two different NSAID molecules. MedlinePlus lists Toradol as a discontinued US brand with generic ketorolac still available. A search for Toradol vs Voltaren is a search for ketorolac vs diclofenac.
Two naming details cause most of the confusion. Toradol in the US referred to oral and injectable ketorolac, not to a topical product, so a compounded topical ketorolac like Ketro RX Pain Gel is not "Toradol gel". And outside the US the diclofenac brand changes name: Voltarol is the UK brand for the same active ingredient that is sold as Voltaren in the US.
Which Is Stronger, Ketorolac or Diclofenac?
No topical head-to-head trial has been published. The closest evidence is oral. A double-blind randomized trial of 198 emergency department patients with acute low back pain found no difference in overall clinical improvement at five days between ibuprofen 600 mg, ketorolac 10 mg and diclofenac 50 mg.
Two separate facts get collapsed into one in most versions of this question. The first is regulatory: ketorolac is available in the US by prescription only, while diclofenac 1% gel is sold both over the counter and under prescription labels. The second is potency class: StatPearls describes ketorolac as having "higher demonstrated potency than most other NSAIDs", and its US tablet label is written for pain "that requires analgesia at the opioid level". We state both, and we do not present the second as the reason for the first.
On dose equivalence, in one oral-route trial in cancer pain (Pannuti 1999), oral ketorolac 10 mg and oral diclofenac 50 mg produced comparable relief. That is an oral study; no topical equivalence data exists.
Is There a Prescription Version of Voltaren?
Yes. Diclofenac 1% gel also carries a prescription label, indicated for "relief of the pain of osteoarthritis of joints amenable to topical treatment, such as the knees and those of the hands". Pennsaid is a prescription diclofenac topical solution indicated for the pain of osteoarthritis of the knee.
The two labels are scoped differently. The OTC Voltaren Arthritis Pain label names six joints, allows four applications a day on no more than two body areas at a time, and says to use it up to 21 days unless a doctor directs otherwise. The prescription diclofenac gel label sets a ceiling of 8 g a day on any one upper-extremity joint, 16 g on any one lower-extremity joint, and 32 g a day across all affected joints, with no 21-day self-treatment limit. Same molecule, same 1% strength, different amount of clinical supervision attached.
Being Precise About Our Own Product
There is no published trial comparing topical ketorolac with topical diclofenac, and Ketro RX Pain Gel has not been tested against Voltaren. Compounded medications are not reviewed by the FDA for effectiveness. What can be said is narrower: the two molecules work through the same COX-inhibition mechanism, ketorolac is available in the US by prescription only, and a compounded gel is prepared per patient rather than at one fixed OTC concentration. A licensed provider can advise where each option fits. Start an online consultation if you want one to review your case.
Prescription Status and Potency Class, Side by Side
Both ketorolac and diclofenac are non-steroidal anti-inflammatory drugs (NSAIDs). They work through the same basic mechanism: inhibiting cyclooxygenase (COX) enzymes to reduce prostaglandin production, which decreases inflammation, pain, and swelling at the tissue level. Mayo Clinic notes that topical NSAIDs can work as well as oral NSAIDs for many people, with fewer systemic side effects. But the similarity between these two specific molecules ends there.
StatPearls describes ketorolac as having "higher demonstrated potency than most other NSAIDs". Its US tablet label is written for the short-term management of "moderately severe acute pain that requires analgesia at the opioid level, usually in a postoperative setting", with combined use capped at 5 days. That systemic label describes oral and injectable ketorolac, not a compounded topical. In one oral-route trial in cancer pain (Pannuti 1999), oral ketorolac 10 mg and oral diclofenac 50 mg produced comparable relief. That is an oral study; no topical equivalence data exists.
Rx
Ketorolac is available in the US by prescription only. Diclofenac 1% gel is the only OTC topical NSAID available in the US. Voltaren sells it, and so do store brands and other labels, including Aspercreme Arthritis Pain (the same molecule at the same strength).
Diclofenac became the first OTC topical NSAID in the US when Voltaren Arthritis Pain was approved for over-the-counter sale in 2020. At 1% concentration, it provides effective relief for mild to moderate musculoskeletal pain. But 1% diclofenac is a fixed, standardized dose designed to be safe for unsupervised consumer use, not to maximize therapeutic potency. That label also limits where it can go: the hand, wrist, elbow, foot, ankle and knee only, which is why bursitis in the hip or shoulder falls outside it.
Compounded topical ketorolac works differently on the supply side rather than the pharmacology side. It is prepared per patient by a compounding pharmacy on a prescriber's order, not mass-produced at one fixed concentration, and the prescriber sets the strength and the dosing. A licensed provider can advise where each option fits: start an online consultation to have one review your case. For a full competitive breakdown, see our roundup of the best Voltaren alternatives compared.
Prescription Ketorolac vs OTC Diclofenac
Both products deliver NSAID medication through the skin. The difference is potency, formulation control, and physician oversight. Here is how prescription-strength topical ketorolac compares to OTC diclofenac 1% on the metrics that matter.
Ketro RX (Ketorolac)
Prescription-strength topical NSAID, compounded per patient by a US pharmacy under physician supervision.
- Prescription-only ketorolac, traditionally reserved for hospital and ED use
- Compounded for site-specific relief
- Compounded per patient (not mass-produced)
- Physician-supervised dosing
- Originally developed by a compounding team that works with professional sports organizations
- Class-level: topical NSAIDs have lower systemic exposure than the same drug taken by mouth
Voltaren (Diclofenac 1%)
OTC topical NSAID at fixed 1% concentration. Available at any pharmacy without a prescription.
- Fixed 1% concentration (no customization)
- Baseline NSAID potency
- Mass-manufactured formula
- No physician oversight required
- Available at any pharmacy or drugstore
- Class-level: topical NSAIDs have lower systemic exposure than the same drug taken by mouth
What the Topical NSAID Evidence Actually Shows
Published, peer-reviewed data on topical NSAID efficacy, ketorolac potency, and the safety profile of topical vs oral delivery. No marketing claims. Just the research.
NNT 3.7
Topical Diclofenac, Acute Musculoskeletal Pain
In a Cochrane review subgroup of two studies (314 participants) testing diclofenac Emulgel for acute musculoskeletal pain, the number needed to treat was 1.8. Across all topical diclofenac formulations in that review it was 3.7. These are diclofenac figures, not ketorolac.
5-17x
Lower Systemic Absorption
Topical NSAIDs produce 5-17x lower peak serum concentrations than oral equivalents. Medication stays where you apply it.
= Placebo
GI Side Effects (Topical)
Systematic review and meta-analysis: topical NSAIDs showed no significant difference in GI adverse events vs placebo (OR 0.96, 95% CI 0.73-1.27).
Ketorolac Potency, Pharmacological Comparison
In one oral-route trial in cancer pain (Pannuti 1999), oral ketorolac 10 mg and oral diclofenac 50 mg produced comparable relief. That is an oral study; no topical equivalence data exists. Separately, StatPearls describes ketorolac as having "higher demonstrated potency than most other NSAIDs" and lists its FDA-approved dose forms as oral, nasal spray, IV and IM. Both statements describe systemic ketorolac.
Pannuti et al., Tumori 1999 (PMID 10363074) and Ketorolac, StatPearls
Topical Ketorolac Gel for Acute Pain: Double-Blind RCT
A 1990 double-blind study compared topical ketorolac 2% gel against placebo and against etofenamate in acute ankle sprain. Of 37 patients admitted, 13 received ketorolac. Ankle volume and visual analogue pain scores fell more in the ketorolac group than in the controls, with statistically significant differences on days 4 and 8. It is a small, single, 35-year-old trial of a 2% gel, not a study of any current product.
Cochrane Review: Topical NSAIDs for Acute Musculoskeletal Pain
The Cochrane Collaboration's systematic review of topical NSAIDs for acute musculoskeletal pain analyzed 61 studies with over 8,000 participants, in sprains, strains, contusions and overuse injuries. In a Cochrane review subgroup of two studies (314 participants) testing diclofenac Emulgel for acute musculoskeletal pain, the number needed to treat was 1.8. Across all topical diclofenac formulations in that review it was 3.7. These are diclofenac figures, not ketorolac. Ketoprofen gel reached 2.5 across 5 studies and 348 participants. Ketorolac appears in the review only as one of the topical NSAIDs studied, with no separate result reported.
Cochrane, Topical NSAIDs for Acute Musculoskeletal Pain, PMC6426435
Topical vs Oral NSAIDs: Safety and Efficacy Meta-Analysis
A 2024 meta-analysis published in PMC compared topical vs oral NSAIDs across multiple pain conditions. Topical NSAIDs demonstrated equivalent efficacy to oral for superficial musculoskeletal conditions while producing significantly fewer systemic adverse events. Topical delivery resulted in 2-8% of the peak serum concentration of oral administration, confirming the localized action mechanism.
What Each Label Covers
Not every pain needs a prescription. The Mayo Clinic's diclofenac guide is a good starting point for understanding what OTC topical NSAIDs can do. Here is an honest framework for when that may be sufficient and when prescription ketorolac makes a meaningful difference. Where you apply it matters as well: the OTC label lists six body areas, and using an anti-inflammatory gel on the neck falls outside them.
What the OTC Voltaren Label Covers
OTC diclofenac 1% is labeled for the temporary relief of arthritis pain in six named joints. The label says the product is not for strains, sprains, bruises or sports injuries, and has not been shown to work for those.
- Arthritis pain in the hand, wrist or elbow
- Arthritis pain in the foot, ankle or knee
- Mild joint stiffness with low inflammation
- Intermittent pain that resolves within a few days
- Preference for no-prescription, immediate access
- Budget is a primary consideration
What People Raise With a Prescriber
Compounded topical ketorolac is a prescription NSAID prepared per patient rather than at one fixed OTC concentration. Start a free consultation and a licensed provider can advise where each option fits.
- Moderate-to-severe pain not adequately controlled by OTC
- Chronic inflammatory conditions (arthritis, TMJ, tendinitis)
- Situations a licensed provider judges suit a compounded prescription topical
- Pain that keeps coming back despite OTC treatment
- Patients who want to avoid oral NSAIDs entirely
- Post-surgical recovery requiring stronger intervention
- Professional athletes and high-performance demands
The Short Version
Voltaren made topical NSAID therapy mainstream. Its OTC label covers arthritis pain in six named joints, four times a day, on no more than two body areas, for up to 21 days without a doctor's direction. Compounded topical ketorolac is a prescription NSAID with no OTC form, prepared per patient. No trial has compared the two, so this page compares labels and access rather than outcomes, and a licensed provider can advise where each option fits.
Beyond Voltaren: Prescription and Daily Pain Relief Options
Prescription-strength anti-inflammatory for pain and flares. Daily topical magnesium for ongoing muscle tension and recovery. Both applied directly where you need them, not through your whole body first. For the full landscape of topical options and mechanisms, read our complete guide to topical pain relief.
Prescription Strength
RX Pain Gel
Compounded topical ketorolac, a prescription NSAID whose systemic forms are used in hospital and emergency department settings. Originally developed by the same compounding team that works with professional sports organizations, including the Boston Red Sox. Compounded per patient by Precision Compounding Pharmacy (US). Applied where it hurts rather than taken by mouth. Online consultation included.
- Ketorolac, a prescription NSAID, compounded per patient
- Applied where it hurts, for localized action
- Dispensed only after a licensed physician reviews your case
- Compounded per order by US pharmacy
- Online physician consultation included
Daily Maintenance
CALM Magnesium Cream
Skincare-formulated topical magnesium for daily muscle tension, soreness, and recovery. Magnesium plays a direct role in muscle relaxation and contraction. Fast-absorbing, non-greasy, no sting. Formulated like premium skincare, not drugstore. No prescription needed.
- Premium transdermal magnesium delivery
- Supports muscle relaxation and recovery
- Fast-absorbing, non-greasy formula
- Formulated like skincare, not drugstore
- No prescription needed
Voltaren vs Ketro RX FAQ
Sources and Citations
- Derry S, Moore RA, Gaskell H, McIntyre M, Wiffen PJ. Topical NSAIDs for acute musculoskeletal pain in adults. Cochrane Database of Systematic Reviews. 2015;(6):CD007402. PMC6426435
- Derry S, Conaghan P, Da Silva JA, Wiffen PJ, Moore RA. Topical NSAIDs for chronic musculoskeletal pain in adults. Cochrane Database of Systematic Reviews. 2016;(4):CD007400. PubMed 27103611
- Kienzler JL, Gold M, Nollevaux F. Systemic bioavailability of topical diclofenac sodium gel 1% versus oral diclofenac sodium in healthy volunteers. Journal of Clinical Pharmacology. 2010;50(1):50-61. PubMed 19841157
- Honvo G, Leclercq V, Geerinck A, et al. Safety of topical non-steroidal anti-inflammatory drugs in osteoarthritis: outcomes of a systematic review and meta-analysis. Drugs & Aging. 2019;36(Suppl 1):45-57. PMC6509095
- Mahmoodi AN, Patel P, Kim PY. Ketorolac. StatPearls. StatPearls Publishing; 2024. NCBI Bookshelf, NBK545172
- Topical ketorolac tromethamine gel for pain relief in ankle sprains: a double-blind, placebo-controlled study. PubMed. PMID: 2105985. pubmed.ncbi.nlm.nih.gov/2105985
- Topical vs Oral NSAID Safety and Efficacy: Systematic Review and Meta-Analysis. PMC. 2024. PMC10980447
- Mayo Clinic. Arthritis pain: Treatments absorbed through your skin. mayoclinic.org
- Mayo Clinic. Diclofenac (topical application route). mayoclinic.org
- Irizarry E, Restivo A, Salama M, et al. A randomized controlled trial of ibuprofen versus ketorolac versus diclofenac for acute, nonradicular low back pain. Academic Emergency Medicine. 2021;28(11):1228-1235. AAFP POEM summary
- Pannuti F, Robustelli della Cuna G, Ventaffrida V, Strocchi E, Camaggi CM. A double-blind evaluation of the analgesic efficacy and toxicity of oral ketorolac and diclofenac in cancer pain. Tumori. 1999;85(2):96-100. PubMed 10363074
- Voltaren Arthritis Pain (diclofenac sodium topical gel 1%) Drug Facts. DailyMed. dailymed.nlm.nih.gov
- Diclofenac sodium topical gel 1%, prescribing information. DailyMed. dailymed.nlm.nih.gov
- Ketorolac tromethamine tablets, prescribing information. DailyMed. dailymed.nlm.nih.gov
- Ketorolac. MedlinePlus, US National Library of Medicine. medlineplus.gov
How Ketro RX Compares to Other Products
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Voltaren Alternative: Conditions That Benefit From Prescription Strength
TMJ / Jaw Pain
The masseter sits close to the surface. Prescription ketorolac applied where it hurts rather than taken by mouth.
Learn More →Arthritis
ACR recommends topical NSAIDs as first-line for knee and hand OA. When OTC diclofenac isn't enough, prescription-strength ketorolac is an option under physician supervision.
Learn More →Back Pain
Back muscles sit close to the surface, which is the usual target for topical anti-inflammatory treatment. A licensed provider can advise where each option fits.
Learn More →Neck & Shoulder
Desk tension, stress knots, and chronic neck pain. Topical delivery to superficial trapezius and cervical muscles.
Learn More →Tension Headaches
Topical NSAIDs applied to temples, forehead, and neck muscles for headache relief without oral medication.
Learn More →DOMS / Muscle Soreness
Post-workout inflammation and delayed onset muscle soreness. Topical anti-inflammatory recovery without pills.
Learn More →A prescription NSAID, compounded per patient, applied where it hurts. Physician review included.
This content is for informational purposes only and does not constitute medical advice. Consult a healthcare provider before starting any new treatment. Individual results may vary. Ketro RX Pain Gel requires a prescription. Voltaren is a registered trademark of GSK Consumer Healthcare. Ketro is not affiliated with Voltaren or GSK. Clinical data referenced from published peer-reviewed studies.
Ketro RX Pain Gel
Prescription-strength alternative to Voltaren