Paracetamol and Ibuprofen With or Without Famotidine for Calcific Tendinitis of the Shoulder

Randomized Controlled Single-Centre Study Evaluating the Efficacy of Therapy With Paracetamol and Ibuprofen, With and Without Famotidine, in the Treatment of Calcific Tendinitis of the Shoulder

This randomized, open-label, single-centre controlled study evaluates the efficacy and safety of combined paracetamol and ibuprofen therapy with versus without famotidine in the treatment of calcific tendinitis of the shoulder. Outcomes include pain reduction, functional improvement, radiological changes, and need for additional interventions over a 12-month follow-up period.

Study Overview

• Status: Not yet recruiting
• Conditions: Calcific Tendinitis
• Intervention / Treatment: Drug: Paracetamol + Ibuprofen + Famotidine; Drug: Paracetamol + Ibuprofen

Detailed Description

Calcific tendinitis of the shoulder is a common cause of acute and chronic shoulder pain, often requiring multimodal treatment. Nonsteroidal anti-inflammatory drugs (NSAIDs) and analgesics such as paracetamol are frequently used as first-line therapy; however, gastrointestinal adverse effects remain a concern. Famotidine, a histamine H2 receptor antagonist, may improve gastrointestinal safety and potentially influence treatment tolerability.

This study is a randomized, open-label, single-centre controlled trial conducted in the emergency surgical outpatient setting. The objective is to compare the efficacy and safety of alternating paracetamol and ibuprofen therapy with the addition of famotidine versus the same analgesic regimen without famotidine in patients with calcific tendinitis of the shoulder.

Participants will be randomized into two groups:

Intervention group: alternating paracetamol (1000 mg) and ibuprofen (400 mg) for 14 days with famotidine 40 mg once daily Control group: paracetamol (1000 mg) and ibuprofen (400 mg) administered concomitantly for 14 days without famotidine Patients on chronic pantoprazole therapy will temporarily switch to famotidine during the intervention period.

The primary outcome is the change in pain and shoulder function measured by the Oxford Shoulder Score (OSS) over 12 months. Secondary outcomes include radiographic changes in calcifications, frequency of additional therapeutic interventions (physical therapy, extracorporeal shockwave therapy, corticosteroid injections, barbotage, and arthroscopic surgery), and treatment safety and tolerability.

Patients will be followed at 2 weeks, 6 weeks, 3 months, and 12 months. Assessments include Visual Analog Scale (VAS), OSS questionnaires, range of motion, and radiographic evaluation at 3 months. Adverse events will be monitored throughout the study.

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Marin Glavčić, MD; Phone Number: +385 01 290 2571; Email: mglavcic@kbd.hr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥18 years
• Clinical history of shoulder pain consistent with calcific tendinitis
• Presence of calcifications confirmed by shoulder X-ray
• Ability and willingness to comply with study procedures and follow-up
• Signed informed consent

Exclusion Criteria:

• Known allergy or hypersensitivity to paracetamol, ibuprofen, or famotidine
• Active gastrointestinal disease contraindicating NSAID use
• Chronic dual antiplatelet therapy
• Current use of proton pump inhibitors other than pantoprazole (unless temporarily replaced)
• Severe systemic diseases that may interfere with study participation or outcomes

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Paracetamol + Ibuprofen + Famotidine; Paracetamol and ibuprofen are administered in an alternating regimen over 14 days. Famotidine is given once daily during the same period. Patients on chronic pantoprazole therapy temporarily switch to famotidine during treatment.	Drug: Paracetamol + Ibuprofen + Famotidine; Participants receive alternating doses of paracetamol (1000 mg) and ibuprofen (400 mg) over a 14-day period, together with famotidine 40 mg once daily. Patients on chronic pantoprazole therapy temporarily switch to famotidine during this period.
Active Comparator: Paracetamol + Ibuprofen (No Famotidine); Paracetamol and ibuprofen are administered concomitantly over 14 days without the addition of famotidine.	Drug: Paracetamol + Ibuprofen; Participants receive paracetamol (1000 mg) and ibuprofen (400 mg) administered concomitantly over a 14-day period without the addition of famotidine.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Oxford Shoulder Score (OSS)	The Oxford Shoulder Score (OSS) is a validated patient-reported questionnaire assessing shoulder pain and function. It consists of 12 items, each scored from 0 to 4, with a total score range of 0 to 48, where higher scores indicate better shoulder function. The primary endpoint is the change in OSS from baseline to follow-up, comparing the two treatment groups.	Baseline to 12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Pain Intensity (Visual Analog Scale, VAS)	Pain intensity is measured using a Visual Analog Scale (VAS), ranging from 0 (no pain) to 10 (worst imaginable pain). The outcome is defined as the change in VAS score from baseline across follow-up time points.	Baseline, 2 weeks, 6 weeks, 3 months, and 12 months
Change in Size of Calcific Deposits on X-ray	Radiographic assessment of calcific deposits in the shoulder using standard X-ray imaging. The outcome measure is the change in size of calcifications (measured in millimeters) from baseline to 3 months.	Baseline to 3 months
Use of Additional Therapeutic Interventions	The proportion of patients requiring additional treatments, including physical therapy, extracorporeal shockwave therapy (ESWL), corticosteroid injections, ultrasound-guided barbotage, or arthroscopic surgery.	Up to 12 months
Incidence of Adverse Events	Number and type of treatment-related adverse events, including gastrointestinal symptoms and other drug-related side effects, recorded throughout the study period.	Baseline to 12 months
Change in Shoulder Range of Motion	Clinical assessment of active range of motion of the affected shoulder (e.g., abduction, flexion, rotation), evaluated over time and compared between groups.	2 weeks, 6 weeks, 3 months, and 12 months
Change in Shoulder Abduction Range of Motion (Degrees)	Active shoulder abduction range of motion is measured in degrees using a goniometer. The outcome measure is the change from baseline at each follow-up time point.	Baseline, 2 weeks, 6 weeks.
Change in Shoulder Flexion Range of Motion (Degrees)	Active shoulder flexion range of motion is measured in degrees using a goniometer. The outcome measure is the change from baseline at each follow-up time point.	Baseline, 2 weeks, 6 weeks

Collaborators and Investigators

• Sponsor: University Hospital Dubrava

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2028

Study Registration Dates

• First Submitted: March 26, 2026
• First Submitted That Met QC Criteria: April 13, 2026
• First Posted (Actual): April 20, 2026

Study Record Updates

• Last Update Posted (Actual): April 20, 2026
• Last Update Submitted That Met QC Criteria: April 13, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Famotidine; Shoulder pain; NSAIDs; Calcific tendinitis
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Musculoskeletal Diseases; Joint Diseases; Arthralgia; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Shoulder Pain; Sulfur Compounds; Organic Chemicals; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Thiazoles; Azoles; Carboxylic Acids; Anilides; Amides; Aniline Compounds; Amines; Acetanilides; Acids, Carbocyclic; Phenylpropionates; Acetaminophen; Ibuprofen; Famotidine
• Other Study ID Numbers: 2025/1024-7

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No