A missed dose is not made up with a double dose. If there are symptoms of too much nicotine, the patient stops taking it and contacts the doctor, and if cravings are strong despite treatment, the doctor checks whether the dose is too low. The details depend on the medicine.
What should you do after missing a dose?
According to the manufacturer of varenicline, taking all doses at the right time throughout the recommended period increases the chance of quitting. The patient takes a forgotten Champix tablet as soon as they remember, unless the next dose is due within 3 to 4 hours. In that case, they skip the missed tablet and do not take a double dose. Bupropion is not taken at more than 150 mg at a time, and at least 8 hours must pass between two doses, so two Zyban tablets are not combined into one dose.
The Summary of Product Characteristics for Desmoxan does not say what to do after missing a cytisine tablet. The treatment schedule does, however, give the maximum daily dose, for example 6 tablets on days 1 to 3 and 5 tablets on days 4 to 12, and the patient does not exceed this dose. The patient talks to a doctor or pharmacist about how to continue cytisine after missing several tablets.
A NiQuitin patch is applied once a day, always at the same time, and not worn for longer than 24 hours, because after that it releases less nicotine. Two patches are never applied at the same time, even if the patient is late changing it. The patient does not use gum, spray or lozenges at fixed times, but when a craving hits, and keeps to the daily limit.
What symptoms suggest too high a dose of nicotine?
According to the manufacturers of nicotine replacement products, symptoms of too high a dose of nicotine can occur in a person who took in little nicotine before treatment, and in a person who takes in nicotine from other sources during treatment, for example by still smoking or using an e-cigarette. The symptoms are similar to those of nicotine poisoning. They include:
- nausea, vomiting and excessive salivation
- abdominal pain and diarrhoea
- pallor and heavy sweating
- headache and dizziness
- hearing disturbances and marked weakness
A patient with such symptoms stops taking nicotine and does not wait for a scheduled appointment, but contacts the doctor straight away. They remove the patch and rinse the skin with plain water, because according to the manufacturer of NiQuitin patches, soap can increase nicotine absorption. Nicotine stored in the skin keeps passing into the blood for several hours after the patch is removed, so symptoms may not go away immediately. Low blood pressure, a weak or irregular pulse, difficulty breathing, extreme exhaustion and seizures can occur after a large dose of nicotine and need immediate medical help.
The manufacturer of the gum and of Nicorette Invisipatch recommends stopping nicotine for a while if there are symptoms of too high a dose, and if they do not go away, using the medicine less often or at a lower dose. If marked side effects do not go away a few days after starting treatment with the NiQuitin 21 mg patch, the manufacturer recommends lowering the dose to 14 mg. The doctor agrees the new dose with the patient.
Can you overdose on cytisine?
Cytisine does not contain nicotine, but according to the manufacturer of Desmoxan, the symptoms of a cytisine overdose are similar to those of nicotine poisoning. They include feeling unwell, nausea, vomiting, a fast heartbeat, changes in blood pressure, breathing and vision problems, and seizures. A patient who has taken more tablets than the treatment schedule allows and has such symptoms needs urgent medical help.
When might the dose of nicotine be too low?
Strong cravings despite treatment may mean the dose of nicotine is too low, but the doctor also checks whether the patient is using the medicine correctly, for example whether they chew the gum as the manufacturer recommends. If a craving does not pass within a few minutes after one spray, the manufacturer allows a second spray. For people who have not stopped smoking while using 2 mg gum, the manufacturer recommends 4 mg gum. For someone for whom a patch alone is not enough, gum, a lozenge or nicotine spray can help with sudden cravings. Such a combination, a higher dose or a change of medicine is decided by the doctor, especially for a person with heart disease, and two patches are never applied at the same time.