Drug Action
Naltrexone is an opioid-receptor antagonist.
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Drug reference
Naltrexone is an opioid-receptor antagonist.
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Adjunct to prevent relapse in formerly opioid-dependent Nervous system patients (who have remained opioid-free for at least 7–10 days) (initiated under specialist supervision) ▶BY MOUTH ▶Adult: Initially 25 mg daily, then increased to 50 mg daily, total weekly dose may be divided and given on 3 days of the week for improved compliance (e.g. 100 mg on Monday and Wednesday, and 150 mg on Friday); maximum 350 mg per week Adjunct to prevent relapse in formerly alcohol-dependent patients (initiated under specialist supervision) ▶BY MOUTH ▶Adult: 25 mg once daily on the first day, then increased if tolerated to 50 mg daily l UNLICENSED USE 25 mg dose for adjunct to prevent relapse in formerly alcohol-dependent patients is an unlicensed dose.
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Patients currently dependent on opioids
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Concomitant use of opioids CAUTIONS, FURTHER INFORMATION ▶Concomitant use of opioids Concomitant use of opioids should be avoided but increased dose of opioid analgesic may be required for pain—manufacturer advises to monitor for opioid intoxication.
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Test for opioid dependence with naloxone before treatment.
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NICE decisions ▶Naltrexone for the management of opioid dependence (January 2007) NICE TA115 Naltrexone is recommended for the prevention of relapse in formerly opioid-dependent patients who are motivated to remain in a supportive care abstinence programme. Nervous system Naltrexone should be administered under supervision and its effectiveness in preventing opioid misuse reviewed regularly. www.nice.org.uk/guidance/ta115
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→Appendix 1: naltrexone
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▶Common or very common Abdominal pain. anxiety. appetite abnormal. arthralgia. asthenia. chest pain. chills . constipation. diarrhoea. dizziness. eye disorders. headache. hyperhidrosis. mood altered. myalgia. nausea. palpitations. sexual dysfunction. skin reactions. sleep disorders. tachycardia. thirst. vomiting ▶Uncommon Alopecia. confusion. cough. depression. drowsiness. dry mouth. dysphonia. dyspnoea. ear discomfort. eye discomfort. eye swelling. feeling hot. fever. flatulence. flushing. hallucination. hepatic disorders. lymphadenopathy. nasal complaints. oropharyngeal pain. pain. paranoia. peripheral coldness. seborrhoea. sinus disorder. sputum increased. tinnitus. tremor. ulcer. urinary disorders. vertigo. vision disorders . weight changes. yawning ▶Rare or very rare Immune thrombocytopenic purpura. rhabdomyolysis. suicidal tendencies ▶Frequency not known Withdrawal syndrome
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Use only if benefit outweighs risk.
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Avoid—potential toxicity.
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Manufacturer advises caution in mild to moderate impairment; avoid in severe or acute impairment, acute hepatitis, or hepatic failure. Dose adjustments Manufacturer advises consider dose adjustment in mild to moderate impairment.
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Avoid in severe impairment.
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Liver function tests needed before and during treatment.
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There can be variation in the licensing of different medicines containing the same drug. Forms available from special-order manufacturers include: capsule, oral suspension, oral solution Tablet ▶Naltrexone hydrochloride (Non-proprietary) Naltrexone hydrochloride 50 mg Naltrexone 50mg tablets | 28 tablet P £70.11 DT = £66.02 ▶Adepend (AOP Orphan Pharmaceuticals AG) Naltrexone hydrochloride 50 mg Adepend 50mg tablets | 28 tablet P £47.43 DT = £66.02 8.2 Nicotine dependence Smoking cessation Overview Smoking tobacco is the main cause of preventable illness and premature death in the UK. It is linked to a number of diseases such as cancer (primarily lung cancer), chronic obstructive pulmonary disease, and cardiovascular disease, and can lead to complications during pregnancy. Smoking cessation reduces the risk of developing or worsening of smoking-related illnesses, and the benefits begin as soon as a person stops smoking. Smoking cessation may be associated with temporary withdrawal symptoms caused by nicotine dependence, making it difficult for people to stop. These symptoms include nicotine cravings, irritability, depression, restlessness, poor concentration, light-headedness, sleep disturbances, and increased appetite. Weight gain is a concern for many people who stop smoking, however it is less likely to occur when drug treatment is used to aid smoking cessation. Non-drug treatment g All smokers, including those who smoke e-cigarettes, should be advised to stop smoking and be offered support to facilitate smoking cessation. They should also be advised that stopping in one step (‘abrupt quitting’) offers the best chance of lasting success, and that a combination of drug treatment and behavioural support is likely to be the most effective approach h’Abrupt quitting’ is when a smoker makes a commitment to stop smoking on or before a particular date (the quit date), rather than by gradually reducing their smoking. g Smokers who wish to stop smoking should be referred to their local NHS Stop Smoking Services, where they will be provided with advice, drug treatment, and behavioural support options such as individual counselling or group meetings. Smokers who decline to attend their local NHS Stop Smoking Services should be referred to a suitable healthcare professional who can also offer drug treatment and practical advice. h Drug treatment Nicotine replacement therapy (NRT), varenicline p. 524, and bupropion hydrochloride p. 521, are effective drug treatments to aid smoking cessation. g The choice of drug treatment should take into consideration the smoker’s likely adherence, preferences, and previous experience of smoking-cessation aids, as well as contra-indications and side-effects of each preparation. Varenicline, or a combination of long-acting NRT (transdermal patch) and short-acting NRT (lozenges, gum, sublingual tablets, inhalator, nasal spray and oral spray), are the most effective treatment options and thus the preferred choices. If these options are not appropriate, bupropion hydrochloride or single therapy NRT should be considered instead. h Nicotine transdermal patches are generally applied for 16 hours, with the patch removed overnight; if smokers experience strong nicotine cravings upon waking, a 24-hour patch can be used instead. Short-acting nicotine preparations are used whenever the urge to smoke occurs or to prevent cravings; there is no evidence that one form of NRT is more effective than another. g The use of NRT combined with varenicline or bupropion hydrochloride is not recommended, and both varenicline and bupropion hydrochloride should not be prescribed together. A quit date should be agreed when drug treatment is prescribed for smoking cessation, and treatment should be available before the person stops smoking. Smokers should be prescribed enough treatment to last 2 weeks after their agreed quit date and be re-assessed shortly before their supply finishes. Smokers who are unwilling or not ready to stop smoking may also benefit from the use of NRT as part of a ’harm reduction approach’, because the amount of nicotine in NRT is much lower and less addictive than in smoking tobacco. Harm reduction approaches include stopping smoking whilst using NRT to prevent relapse, and smoking reduction or temporary abstinence with or without the use of NRT. These smokers should be advised that NRT will make it easier to reduce how much they smoke and improve their chance of stopping smoking in the long-term. h E-cigarettes E-cigarettes deliver nicotine without the toxins found in tobacco smoke. Evidence suggests that e-cigarettes are substantially less harmful to health than tobacco smoking, but long-term effects are still largely unknown. Some smokers have found e-cigarettes useful for smoking cessation, however they cannot be prescribed or supplied by smoking cessation services. g People who wish to use e- cigarettes should be advised that although these products are not licensed drugs, they are regulated by the Tobacco and Related Products Regulations 2016. h In the UK, sale of e- cigarettes is prohibited in children under 18 years of age. Pregnancy g Pregnant females should be advised to stop smoking completely, and be informed about the risks to the unborn child of smoking during pregnancy, and the harmful effects of exposure to second-hand smoke for both mother and baby. All pregnant females who smoke or have stopped smoking in the last 2 weeks should be referred to their local NHS Stop Smoking Services, and ongoing support should be offered during and following pregnancy. Smoking cessation should also be encouraged for all members of the household. Pregnant females who smoke should be advised to contact the NHS Pregnancy Smoking Helpline for further information (Tel: 0800 169 9169). NRT should only be used in pregnant females if non-drug treatment options have failed. Clinical judgement should be used when deciding whether to prescribe NRT following a discussion about its risks and benefits. Subsequent prescriptions should only be given to pregnant females who have demonstrated they are still not smoking. h Concomitant drugs Polycyclic aromatic hydrocarbons found in tobacco smoke increase the metabolism of some drugs by inducing hepatic enzymes, often requiring an increase in dose. Information about drugs interacting with tobacco smoke can be found under Interactions of the relevant drug monograph. Useful Resources Stop smoking interventions and services. National Institute for Health and Care Excellence. NICE guideline 92. March 2018. www.nice.org.uk/guidance/ng92 Smoking: harm reduction. National Institute for Health and Care Excellence. Public health guidance 45. June 2013. www.nice.org.uk/guidance/ph45 National Centre for Smoking Cessation and Training. www.ncsct.co.uk ANTIDEPRESSANTS › SEROTONIN AND NORADRENALINE RE-UPTAKE INHIBITORS
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Patients should be warned that an attempt to overcome the blockade of opioid receptors by overdosing could result in acute opioid intoxication.
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Initially 25 mg daily, then increased to 50 mg
First-line fragment. Read the complete Indications and Dose section above.
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25 mg once daily on the first day, then increased
First-line fragment. Read the complete Indications and Dose section above.
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