A suspected case of paralytic shellfish poisoning has prompted health officials to warn people not to eat shellfish collected from Onetangi Beach on Waiheke Island.
The person became ill an hour after eating pipis on Sunday, the Auckland Regional Public Health Service (ARPHS) said.
The patient's symptoms included dizziness, tingling of fingers and toes, tingling and swelling of the tongue, nausea and diarrhoea.
The Ministry for Primary Industries was to take shellfish samples from the beach, and hoped to have results by next week.
In the meantime, Medical Officer of Health Simon Baker urged people to exercise caution.
"While this is not a confirmed case, all the symptoms are consistent with PSP [paralytic shellfish poisoning] therefore ARPHS strongly urges people not to collect or eat any shellfish from Onetangi Beach until test results are known," Dr Baker said.
PSP occurs within 12 hours of eating affected shellfish. Other symptoms include double vision, slurred or unclear speech and, in severe cases, paralysis and respiratory failure.
If anyone experiences symptoms after eating shellfish, call 111 immediately, keep any leftover shellfish so it can be tested, and contact ARPHS on 09 623 4600, Dr Baker said.
"ARPHS also wishes to hear from anyone else who may have experienced any of these symptoms after eating shellfish."
The service would monitor the situation and issue an update once the test results came back, Mr Baker said.