The mother of a 16-year-old who took her own life by overdosing on anti-anxiety pills has told a Holyrood committee there is a fault in the healthcare system which is "letting young people down".

Annette McKenzie wants the law to be changed so under-18s cannot be prescribed medication to treat mental health issues without parental consent.

She found out her daughter Britney had been prescribed the medication by her GP after she died of an overdose of the tablets in July last year.

Ms McKenzie, from Glasgow, has lodged a petition at the Scottish Parliament.

Speaking at the Public Petitions Committee, she said her campaign is not a "witch-hunt" against the doctor who treated her daughter.

"When this happened with Britney, yes I was devastated, I was broken, but it also let me find a fault in the system where it is letting young people down," she told MSPs.

Britney, who suffered from depression and anxiety and was having suicidal impulses, was prescribed a month's supply of the drug by her doctor last June. Sixteen days later, she took an overdose.

Ms McKenzie said she had been unaware of the prescription, and had mistaken side-effects such as tiredness as her daughter being lazy.

"My daughter didn't understand at 16 years old the severity and strength of the medication she was given," she said.

"She went to the doctor that day to ask for help, she didn't go expecting to be given pills."

She added: "I know a lot of people have concerns that my petition in particular will discourage young people from going to seek help from their doctor.

"To say that a child won't go to the doctor to ask for help, I don't believe that, because a child at that age isn't going to a doctor to ask for pills, they are going to speak out, to be asked to be helped."

GPs do not need to seek parental consent to prescribe medication if the young person is deemed to be able to understand the nature of the treatment and potential consequences of the treatment.

Ms McKenzie said the strength and effect of some mental health medications make it important that parents and guardians are "fully involved and aware of the circumstances, allowing them to support treatment" and safeguard their children by taking control of pills of dispensing them as required.

"We're not just talking about my daughter being 16 here, we are talking about there being no age of consent," she said.

"If they deem you to be wise enough, they will send you away with medication."

The committee agreed to contact the Scottish Government, the Scottish Association for Mental Health, the General Medical Council and a range of other relevant organisations.