Hypersensitivity reactions
Potassium para-aminobenzoate 3 g powder must be discontinued immediately if signs or symptoms of hypersensitivity reactions develop (including, but not limited to, severe rash or rash accompanied by raised liver enzymes, fever, general malaise, fatigue, muscle pain, blisters, oral lesions, oedema and eosinophilia) and must not be restarted.
Severe cutaneous adverse reactions
Severe cutaneous adverse reactions (SCARs) manifesting as drug reactions with eosinophilia and systemic symptoms (DRESS), which can be life-threatening or fatal, have been reported in association with Potassium para-aminobenzoate 3 g powder treatment. At the time of prescription, patients should be advised of the signs and symptoms and monitored closely for skin reactions.
If signs and symptoms suggestive of this reaction appear, Potassium para-aminobenzoate 3 g powder should be withdrawn immediately.
If the patient has developed DRESS with the use of Potassium para-aminobenzoate 3 g powder, treatment with Potassium para-aminobenzoate 3 g powder must not be restarted in this patient at any time.
Food intake
Treatment with Potassium para-aminobenzoate 3 g powder should be interrupted during periods of low food intake (e.g. during fasting, anorexia, nausea). This is to avoid the possible development of hypoglycaemia. (see section 4.8).
Hyperkalaemia
In patients with impaired renal function or other diseases like diabetes mellitus, cardiovascular diseases, congestive heart failure, hypoaldosteronism and pseudohypoaldosteronism and/or in case of concomitant treatment with medicinal products that can increase the serum potassium level (see section 4.5), Potassium para-aminobenzoate 3 g powder should be used with caution because of the risk of hyperkalaemia.
Before start of treatment with Potassium para-aminobenzoate 3 g powder, an anamnestic survey of pre-existing hyperkalaemia risk factors including an initial serum potassium determination should be performed for all patients. For patients with an increased risk of hyperkalaemia, serum potassium should be measured at least monthly or at closer intervals depending on risk assessment and monitoring requirements due to other risk factors. For patients with an increased initial serum potassium level, the underlying cause should be identified insofar as possible and serum potassium levels should be normalised before start of treatment with Potassium para- aminobenzoate 3 g powder. For these patients, monitoring after start of therapy should also be performed monthly until long-term normal serum potassium levels are established. After that and for all other patients, monitoring is recommended at least quarterly.
Furthermore, serum potassium should be measured promptly for patients who report symptoms possibly indicative of hyperkalaemia such as muscle pain or tightness, flaccid paralysis, weakness, paraesthesia, nausea, vomiting, palpitations, bradycardia or tachypnoea.
Liver dysfunction
Hepatotoxic effects have been observed for Potassium para-aminobenzoate 3 g powder and were reported as hepatitis (various specifications), drug-induced liver injury or (acute) hepatic failure depending on results of diagnostic investigations, time course of drug use and liver disorder and other accompanying symptoms such as nausea, pyrexia, chromaturia or jaundice. For all patients who take Potassium para-aminobenzoate 3 g powder, regular (at least every 4 weeks) liver function tests must be performed (transaminases, gamma-GT, ALP, LDH, bilirubin). If elevated liver function tests or symptoms indicative of a liver disorder are observed, Potassium para- aminobenzoate 3 g powder must be discontinued immediately.