The claims of using the "right product for your symptoms" and that the products were specifically formulated for different types of pain were repeated on the website www.nurofen.co.nz.
However, the pain specific products contained the same active ingredient, ibuprofen lysine, and were equally effective in treating any of the types of pain but cost more than regular Nurofen.
The claims were uncovered after an investigation by the Commerce Commission in 2015 and once the charges were laid the company agreed to re-label pain specific Nurofen products which were removed from sale by March last year.
The watchdog said the packaging stated the products "targeted" a particular type of pain, "when this was not the case".
Prosecutor Nick Flanagan said when the misleading claims were removed consumers were left with a "very different product" which was less attractive and similar to much cheaper options.
The commission was also concerned about "double dosing" by people buying one variety for back pain and then taking another for a migraine, Flanagan said.
However, Reckitt Benckiser's lawyer, Michael Heron QC, noted the statement on the back of the pack provided a warning not to take the product with other ibuprofen products.
The company "sincerely regrets" the packaging and apologised on its behalf to anyone who was misled, the lawyer said.
It was never the multinational corporation's intention to breach the Fair Trading Act or mislead consumers.
Instead, the distributor wanted to help consumers navigate different pain relief products.
"If it loses the trust of consumers that's contrary to its interests," Heron said.
However, the drug giant accepted the claims were "careless" but didn't go as far as to say they were false.
Judge June Jelas said Reckitt Benckiser's offending was "blatant misleading conduct" and the company needed to be held accountable.
A high level of trust is placed on claims placed on pain relief products, but the distributor breached that trust and said the "premium" price strongly suggested that profit was the motivator for the claims, the judge said.
Judge Jelas also criticised the company's failure to respond "in a more prompt way" to "severe" public criticism of the advertising, including a Herald on Sunday article from 2011.
It was only after charges were laid that the company addressed the misleading claims and withdrew its products. She didn't find any mitigating factors in the offending.
The judge fined the drug giant a total of $1.08 million for all of the 10 charges.
Reckitt Benckiser was also ordered to pay $1500 in court costs.
In Australia last year, Reckitt Benckiser was handed an A$1.7m fine for the same misleading claims but the country's watchdog appealed and the fine was increased to A$6m in December.
The company is appealing this decision.
Consumer NZ chief executive Sue Chetwin applauded the Commerce Commission for the prosecution but said the fine imposed was minimal.
"A million dollars is quite small compared to the detriment done to consumers."
Chetwin believed Reckitt Benckiser knew the labels were misleading.
"At the end of the day it was just a marketing ploy to get more people to buy their products."
She warned people to take advertising, especially on pharmaceuticals, with a grain of salt.
OTHER COMPANIES FINED FOR MISLEADING CONSUMERS:
YOUI - fined $320,00 in December for misleading sales techniques.
YOGHURT STORY - fined $270,000 in October for falsely claiming products were yoghurt.
TRUSTPOWER LIMITED - fined $390,000 in September for misleading broadband offer.
