All non-steroidal anti-inflammatory preparations are characterized by gastrointestinal bleeding, ulcers and perforations, which can be fatal, occur during treatment against the background of warning symptoms (or in the absence of them) or in patients with a history of serious gastrointestinal events. In general, such phenomena are most dangerous for elderly patients. When patients using diclofenac sodium develop these complications, the preparation should be discontinued.

During preparation therapy, patients with symptoms indicating diseases of the gastrointestinal tract, as well as those with a history of stomach or duodenal ulcer, patients with ulcerative colitis or Crohn's disease, patients with impaired liver function.

To reduce the risk of toxic effects on the gastrointestinal tract in patients with a history of ulceration, in particular, complicated bleeding and perforation, as well as in elderly patients, treatment should be started with the lowest effective dose and followed.

Due to its pharmacodynamic properties, diclofenac sodium, like other non-steroidal anti-inflammatory preparations, can mask the signs and symptoms characteristic of infectious and inflammatory diseases. Fever in itself is not an indication for the use of the preparation.

For patients receiving concomitant therapy with acetylsalicylic acid or other preparations that may increase the risk of side effects, combination therapy with protective agents (eg, proton pump inhibitors) should be considered. In patients who receive concomitant therapy with systemic corticosteroids, the frequency of undesirable gastrointestinal effects may increase, and with simultaneous use with anticoagulants or antiplatelet agents, there is a risk of bleeding. It is necessary to refrain from the simultaneous reception of diclofenac sodium with other non-steroidal anti-inflammatory preparations, including cyclooxygenase-2 inhibitors.

Nonsteroidal anti-inflammatory preparations may increase the risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke, which may be fatal, and therefore diclofenac sodium is not recommended for the treatment of postoperative pain after coronary artery bypass grafting.

Severe, even fatal, skin reactions, including exfoliative dermatitis, Stevens-Johnson syndrome, and toxic epidermal necrolysis, have been reported very rarely with the use of NSAIDs, including diclofenac sodium. The highest risk of these reactions exists at the beginning of therapy, and the development is noted mainly in the first month of treatment. Diclofenac sodium should be discontinued at the first manifestations of skin rash, mucosal ulcers, or any other manifestations of hypersensitivity.

Patients with asthma, seasonal allergic rhinitis, edema of the nasal mucosa, chronic obstructive pulmonary disease, or chronic respiratory tract infections are more likely to experience allergic reactions (eg, bronchospasm) to NSAIDs than other patients. Therefore, special care is required for the treatment of such patients.

As with treatment with other non-steroidal anti-inflammatory preparations, the level of one or more liver enzymes may increase. With long-term therapy with diclofenac sodium, regular examination of liver functions is indicated. If liver function abnormalities persist or worsen, if signs or symptoms suggestive of liver disease develop, and if other side effects (eg, eosinophilia, rash) occur, "Diclofenac-Pharmex" should be discontinued. preparation-induced hepatitis can occur without prodromal symptoms. Caution is necessary when prescribing diclofenac sodium to patients with hepatic porphyria, as the preparation can provoke its attacks.

Since prostaglandins play an important role in maintaining renal blood flow, special caution is required when treating with rectal suppositories "Diclofenac" patients with impaired heart or kidney functions (including functional renal failure against the background of hypovolemia, nephrotic syndrome, lupus), patients with arterial hypertension in the anamnesis, elderly patients, patients who use diuretics, as well as patients with a significant decrease in the volume of circulating plasma of any etiology (for example, before and after massive surgical interventions). In such cases, during the use of diclofenac sodium as a precautionary measure, regular monitoring of kidney function is recommended. After discontinuation of the preparation, kidney function usually returns to the initial level.

During long-term therapy with diclofenac sodium, as well as when using other non-steroidal anti-inflammatory preparations, it is recommended to monitor the state of peripheral blood.