A police statement said: "On 18 March at around 10.20am, Rebecca Mitchell of Cuttinglye Road, ploughed head on into an oncoming car on Antlands Lane, Horley.
"When paramedics arrived at the scene, Ms Mitchell disclosed that before getting in her car she had taken both cocadamol and tramadol, causing her judgement to become dangerously impaired.
"The driver of the other vehicle, a lady in her 60s, was taken to hospital with serious injuries including multiple abrasions and two fractures.
"At sentencing, Mitchell was also given an 8 month prison sentence (suspended for two years), a 3 month curfew and ordered to pay £450 in costs. Mitchell will also have to do an extended driving test once her disqualification from driving is up."
The Investigating Officer, PC Martin Wilson, said: “Driving whilst under the influence of drugs is extremely dangerous to not only yourself but also other road users. Just because a drug may be prescribed to you does not mean it is safe to use and then drive – you should always read the instruction on the packet or check with your doctor. Drug driving will not be tolerated in Surrey and this sentence demonstrates that.
“If you believe someone you know may be driving whilst on drugs and you think it may be an emergency please call 999. If the situation is not immediate, then please let us know by calling 101. Together we can save lives on the roads.”