Section 1: Introduction -- The Patient Who Left With Three Problems

A 66-year-old man in Kingston presents with chronic knee pain from osteoarthritis. He has hypertension managed with lisinopril 20 mg and hydrochlorothiazide 25 mg. His eGFR is 52. He has a history of peptic ulcer disease, treated and healed two years ago.

He is prescribed diclofenac 50 mg three times daily.

The diclofenac introduces three new risks to a patient who presented with one complaint. First, it opposes the antihypertensive effect of his lisinopril through sodium and water retention -- his blood pressure, previously controlled, will rise. Second, it combines with the lisinopril and hydrochlorothiazide to form the triple whammy (Report 2, Section 4) -- the convergent assault on renal blood flow that is the single most preventable cause of acute kidney injury in Caribbean primary care. Third, it carries a significant risk of reactivating his healed peptic ulcer -- NSAIDs are the most common pharmacological cause of upper GI bleeding.

Paracetamol 1 g four times daily would have addressed his pain without introducing any of these risks.

This is not an unusual prescription. It is a routine analgesic choice made every day in Caribbean clinical practice. The gap is not between what clinicians know about pain management and what they prescribe -- it is between the convenience of reaching for an NSAID and the discipline of choosing the analgesic that fits the patient.

1.1 Pain management in the Caribbean context

Three features of Caribbean practice shape analgesic prescribing:

Over-the-counter NSAID availability. Ibuprofen and diclofenac are available without prescription across the Caribbean. Patients self-medicate for headaches, musculoskeletal pain, menstrual pain, and dental pain -- often without informing their clinician. The clinician's prescribed analgesic may therefore be layered on top of an OTC NSAID the patient is already taking, creating unrecognised therapeutic duplication (Report 1, Section 6).

Limited access to specialist pain services. Chronic pain management -- particularly neuropathic pain, cancer pain, and complex regional pain -- often falls to primary care clinicians without specialist backup. The available formulary may not include the optimal agent, and the clinician must work with what is accessible.

Cultural and economic factors. Injectable analgesics are perceived by some patients as more effective than oral formulations. Opioid prescribing carries stigma in some Caribbean communities and regulatory barriers in others. These factors influence both patient expectations and prescribing patterns.

1.2 What this report covers

This report maps the analgesic options available in Caribbean practice against their clinical risks, organ function requirements, drug interactions, and patient-specific contraindications. It is organised by analgesic class: paracetamol, NSAIDs, opioids, neuropathic pain agents, and adjuvant analgesics. Each class profile includes the clinical evidence for use, the specific risks, the patients in whom the drug should be avoided, and the interactions flagged by ElesRx.

The report concludes with a quick-reference analgesic selection table organised by pain type and patient profile.

Section 2: Paracetamol -- The Underused First Line

2.1 Why paracetamol is undervalued in Caribbean practice

Paracetamol (acetaminophen) is the safest systemic analgesic available. It does not affect renal blood flow, does not inhibit platelets, does not cause GI bleeding, does not interact with antihypertensives, and does not require renal dose adjustment. At appropriate doses, it is effective for mild-to-moderate pain and is the recommended first-line analgesic for osteoarthritis, headache, dental pain, and post-operative pain.

Despite this, paracetamol is frequently bypassed in Caribbean prescribing in favour of NSAIDs -- perceived as "stronger" by both clinicians and patients. The evidence does not consistently support this perception. For osteoarthritis, systematic reviews demonstrate that paracetamol provides meaningful pain relief, and while NSAIDs show a modest statistical advantage in some trials, the clinical difference is small and must be weighed against the substantially higher adverse effect profile.

2.2 Dose limits and hepatic risk

Paracetamol's safety is dose-dependent. The maximum daily dose in adults with normal hepatic function is 4 g (1 g four times daily). In hepatic impairment (Report 2, Section 5), the maximum is 2 g daily. In severe hepatic disease, paracetamol should be avoided entirely.

Paracetamol overdose -- whether intentional or through cumulative excess -- is the most common cause of acute liver failure worldwide. The risk in Caribbean practice is compounded by the availability of multiple paracetamol-containing combination products (paracetamol + codeine, paracetamol + tramadol, paracetamol + caffeine). A patient taking a combination product alongside plain paracetamol may exceed the daily maximum without realising it.

Clinicians should ask specifically about all paracetamol-containing products when prescribing or recommending paracetamol.

Section 3: NSAIDs -- The Risks That Follow the Convenience

3.1 The NSAID landscape in the Caribbean

Non-steroidal anti-inflammatory drugs are the most commonly used analgesics in the Caribbean. Diclofenac and ibuprofen are available over the counter. Naproxen, meloxicam, indomethacin, piroxicam, ketorolac, and mefenamic acid are prescribed routinely. They are effective for inflammatory pain, musculoskeletal pain, renal colic, dysmenorrhoea, and post-operative pain.

They also carry a risk profile that is disproportionate to many of the conditions for which they are prescribed.

3.2 Gastrointestinal risk

All non-selective NSAIDs increase the risk of upper GI bleeding and peptic ulceration. The risk is dose-dependent, duration-dependent, and increases with age. Patients aged 65 and older are at highest risk (Report 1, Section 4 -- Beers Criteria). Concurrent use with corticosteroids, anticoagulants, or antiplatelet agents further elevates the risk.

The GI risk varies by agent. Ibuprofen at low doses (1200 mg/day or less) carries the lowest GI risk among non-selective NSAIDs. Diclofenac, naproxen, and piroxicam carry higher risk. Indomethacin and ketorolac carry the highest risk and are associated with the greatest incidence of GI adverse events.

Gastroprotection with a PPI reduces but does not eliminate the GI risk. If an NSAID is required in a patient with GI risk factors, a PPI should be co-prescribed -- but the long-term PPI use that often follows (Report 4, Drugs 1-2) is itself a deprescribing concern.

3.3 Cardiovascular risk

All NSAIDs (except aspirin) are associated with increased cardiovascular risk -- myocardial infarction, stroke, and heart failure exacerbation. The risk is dose-dependent and duration-dependent. Diclofenac carries the highest cardiovascular risk among commonly used NSAIDs, comparable to selective COX-2 inhibitors. Naproxen appears to carry the lowest cardiovascular risk, though it is not risk-neutral.

In patients with established cardiovascular disease, heart failure, or multiple cardiovascular risk factors, NSAIDs should be avoided where possible. If required, naproxen at the lowest effective dose for the shortest duration is the least unfavourable option.

3.4 Renal risk

NSAIDs reduce renal prostaglandin synthesis, decreasing renal blood flow and glomerular filtration. In patients with pre-existing renal impairment, volume depletion, or concurrent use of ACE inhibitors/ARBs and diuretics, this can precipitate acute kidney injury. The triple whammy (ACE/ARB + diuretic + NSAID) is documented in Report 2, Section 4.

NSAIDs should be avoided in patients with eGFR below 30. In patients with eGFR 30-60, they should be used at the lowest dose for the shortest duration with renal function monitoring.

3.5 The OTC problem

The clinical risks described above apply regardless of whether the NSAID was prescribed or purchased over the counter. A patient who buys ibuprofen from a pharmacy and takes it alongside their prescribed medications is exposed to the same interaction and organ function risks as if the ibuprofen had been prescribed.

The difference is that OTC use is invisible to the clinician. The medication history does not capture it. The interaction checker does not see it. The renal function check does not account for it.

Clinicians should ask specifically about OTC analgesic use -- including brand names, which patients may not recognise as NSAIDs -- at every medication review.

Section 4: Opioids -- When They Are Indicated, When They Are Not

4.1 The opioid position in Caribbean practice

Opioid prescribing in the Caribbean occupies a different space from North America or Europe. The opioid overprescribing crisis that has affected the United States has not been replicated in the Caribbean to the same degree, partly because of more restrictive regulatory frameworks, limited formulary availability, and cultural factors that influence both prescribing and patient acceptance.

This does not mean that opioid risks are absent in Caribbean practice. Tramadol and codeine-containing products are widely available and commonly prescribed. Misuse, dependence, and adverse effects occur. The clinical challenge is to use opioids appropriately -- neither overprescribing them (as has occurred in other settings) nor underprescribing them in patients with genuine pain that requires opioid analgesia (cancer pain, severe acute pain, palliative care).

4.2 Tramadol

Tramadol is the most commonly prescribed opioid in Caribbean primary care. It occupies a unique pharmacological position -- it is both a weak mu-opioid agonist and a serotonin-norepinephrine reuptake inhibitor.

This dual mechanism creates a broader interaction and adverse effect profile than its perceived "mild" classification suggests:

• Seizure risk. Tramadol lowers the seizure threshold, particularly at higher doses and in patients with predisposing factors (epilepsy, concurrent serotonergic drugs, alcohol withdrawal).
• Serotonin syndrome. Combination with SSRIs, SNRIs, MAOIs, or other serotonergic agents carries a risk of serotonin syndrome -- a potentially life-threatening condition.
• Hypoglycaemia. Tramadol is associated with hypoglycaemia, particularly in the first days of treatment. In diabetic patients -- the population most likely to also have neuropathic pain -- this risk is clinically significant and frequently unrecognised.
• Renal accumulation. Tramadol and its active metabolite accumulate in renal impairment (Report 2, Section 3). At CrCl below 30, the dose should not exceed 200 mg daily.
• CYP2D6 dependence. Tramadol is a prodrug activated by CYP2D6. Poor metabolisers receive limited analgesic benefit. Ultra-rapid metabolisers produce excessive active metabolite, increasing adverse effects. CYP2D6 polymorphism varies by ethnic population and is relevant to Caribbean demographics.

4.3 Codeine

Codeine is a prodrug entirely dependent on CYP2D6 for conversion to morphine. It shares the CYP2D6 pharmacogenomic variability described for tramadol -- poor metabolisers receive no analgesic benefit, and ultra-rapid metabolisers are at risk of toxicity.

In breastfeeding women, codeine is associated with a documented risk of neonatal morphine toxicity in ultra-rapid metabolisers (Report 5, Section 4).

Codeine-containing combination products (codeine + paracetamol, codeine + ibuprofen) are widely available in Caribbean pharmacies. The combination with ibuprofen carries the same NSAID risks described in Section 3 -- a fact that may be obscured by the brand name.

4.4 Morphine, oxycodone, and strong opioids

For severe acute pain, cancer pain, and palliative care, strong opioids remain the standard of care. Morphine is the reference opioid and is available across the Caribbean, though access and regulatory requirements vary by territory.

All strong opioids share a common adverse effect profile: constipation (which does not resolve with tolerance -- prophylactic laxatives are indicated from initiation), sedation, respiratory depression, nausea, and dependence with prolonged use.

The clinical decision is not whether strong opioids are appropriate -- for severe pain they are -- but whether the duration of use is appropriate. Opioids initiated for acute pain (post-surgical, trauma, renal colic) should have a defined stop date. The absence of a stop date is the most common route to unintended long-term opioid use.

Section 5: Neuropathic Pain -- A Different Mechanism, Different Drugs

5.1 Why standard analgesics do not work for neuropathic pain

Neuropathic pain -- pain arising from nerve damage rather than tissue inflammation -- does not respond to NSAIDs or paracetamol in most cases. The mechanism is different: damaged nerves generate abnormal electrical signals that are interpreted as pain regardless of peripheral inflammation. Standard analgesics target inflammation; neuropathic pain agents target the abnormal nerve signalling.

In the Caribbean, neuropathic pain is most commonly encountered as diabetic peripheral neuropathy, post-herpetic neuralgia (following shingles), and HIV-associated neuropathy.

5.2 Gabapentin and pregabalin

Gabapentin and pregabalin are first-line agents for neuropathic pain in most guidelines. Both bind to the alpha-2-delta subunit of voltage-gated calcium channels, reducing excitatory neurotransmitter release and dampening abnormal nerve signalling.

Both are almost entirely renally cleared and require dose adjustment at CrCl below 60 (Report 2, Section 3). In the diabetic patient with neuropathy and declining renal function, the standard starting dose may be too high.

Common adverse effects include sedation, dizziness, peripheral oedema, and weight gain. These are dose-dependent and more pronounced in older adults.

5.3 Amitriptyline

Amitriptyline at low doses (10-25 mg at night) has established efficacy for neuropathic pain. It is widely used in Caribbean practice for this indication.

It also carries an ACB score of 3 (Report 1, Section 5) and is flagged by the Beers Criteria for adults aged 65 and older (Report 1, Section 4). In older patients, the anticholinergic burden -- confusion, dry mouth, urinary retention, constipation, falls, and an association with cognitive decline -- may outweigh the analgesic benefit.

The clinical decision depends on the patient's age, comorbidities, and current anticholinergic burden. In younger adults without contraindications, low-dose amitriptyline remains a reasonable option. In older adults, gabapentin or pregabalin (with renal adjustment) are associated with a lower overall risk profile.

5.4 Duloxetine

Duloxetine is an SNRI with established efficacy for diabetic neuropathic pain and fibromyalgia. It is contraindicated at CrCl below 30 (Report 2, Section 3). It is not available on all Caribbean formularies, which limits its practical utility in some territories.

Section 6: Adjuvant Analgesics and Topical Options

6.1 Topical NSAIDs

Topical diclofenac and topical ibuprofen provide local anti-inflammatory and analgesic effects with substantially lower systemic exposure than oral formulations. For localised musculoskeletal pain (knee osteoarthritis, soft tissue injuries), topical NSAIDs offer an alternative that avoids the GI, cardiovascular, and renal risks of oral NSAIDs.

Topical NSAIDs are underused in Caribbean practice. Where available, they should be considered before oral NSAIDs for localised pain in patients with GI, cardiovascular, or renal risk factors.

6.2 Capsaicin

Topical capsaicin (0.025-0.075%) depletes substance P from peripheral nerve endings, reducing pain signalling. It is effective for osteoarthritis pain and post-herpetic neuralgia. The initial burning sensation on application limits patient acceptance, but this diminishes with repeated use over 1-2 weeks.

6.3 Corticosteroid injections

Intra-articular corticosteroid injections provide localised anti-inflammatory and analgesic effects for joint pain (knee, shoulder, hip). They are available in most Caribbean secondary care settings. Efficacy is well-established for short-term relief (4-8 weeks). Repeated injections at the same site are associated with cartilage damage and should be limited.

Section 7: Analgesic Selection by Pain Type and Patient Profile

Quick-reference table. Print and use at the point of care.

One principle: Match the analgesic to the pain type, the patient's organ function, their current medication list, and their age. The safest analgesic is the one that addresses the pain without introducing new risks.

Section 8: Drug Interactions -- The Analgesic Blind Spot

Analgesics are frequently added to existing medication lists during acute episodes -- precisely the clinical scenario where interaction checking is most likely to be skipped. Key interactions flagged by ElesRx:

Section 9: About ElesRx

ElesRx includes interaction checking for all analgesic classes covered in this report. When a clinician adds an analgesic to a patient's medication list, the system cross-references it against existing prescriptions, renal function, hepatic function, age, and Beers Criteria status. The triple whammy, NSAID-anticoagulant interactions, and serotonin syndrome risk with tramadol are flagged automatically.

The tool is available at elesrx.com. ElesRx is a product of PIPPS Smart Apps, a division of J.C. Epiphany Limited (Jamaica, est. 1998).

Section 10: Methodology and References

10.1 Data sources

Analgesic safety data and drug interactions are drawn from the ElesRx clinical database, verified against DailyMed, the European Medicines Agency, Health Canada, LiverTox, and published clinical guidelines. Renal and hepatic adjustment data cross-references Report 2. Beers Criteria data cross-references Report 1. The source hierarchy and licensing constraints are the same as Reports 1-6.

10.2 Limitations

This report covers the analgesic classes most commonly encountered in Caribbean outpatient and general ward practice. Specialised pain management (interventional procedures, regional anaesthesia, complex opioid rotations) is beyond its scope.

Analgesic prescribing requires individualised assessment of pain type, severity, patient comorbidities, organ function, and concurrent medications. This report provides general guidance based on published evidence.

10.3 Author and conflict of interest disclosure

This report was authored by Juliet Duncan, BPharm, founder of J.C. Epiphany Limited and developer of ElesRx. The author has a commercial interest in ElesRx. This report is published without an access gate as a contribution to Caribbean clinical education. No external funding was received.

10.4 Citation

Duncan J. The Pain Report: Safer Analgesic Choices in Caribbean Practice. ElesRx Clinical Reports, Report 7. Published 2026 at elesrx.com/reports/pain-report/. J.C. Epiphany Limited, Jamaica.

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