Paracetamol Codeine

Tylex (Codeine/Paracetamol). Schwartz Pharma Ltd. UK Summary of product characteristics, October 2006. 

Muskel Trancopal cum codeino (Winthrop)-comb. with paracetamol and codeine phosphate wfm Alinam (Lucien) wfm... 

Co-codamol is a combination of paracetamol (nonnapioid analgesic) and codeine (opioid analgesic). One of the side-effects of opioids is constipation. Naprosyn is a proprietary (trade name) preparation of the non-steroidal antiinflammatory drug naproxen Adalat is a proprietary preparation of the calcium-channel blocker nifedipine Amoxil is a proprietary preparation of the beta-lactam amoxicillin and Dulco-lax is the brand name of the stimulant laxative bisacodyl. 

Alternative products to diclofenac include naproxen and mefenamic acid, both of which are non-steroidal anti-inflammatory drugs. Co-codamol is a mixture of the opioid analgesic codeine and paracetamol and it does not possess the anti-inflammatory component. It may be used in pain management either where NSAIDs are contraindicated or in patients who are intolerant to the effects of NSAIDs. 

Uniflu paracetamol, diphenhydramine, phenylephrine, codeine, caffein ascorbic acid... 

There are some additional choices in patients with refractory arthritis despite the use of NSAIDs or paracetamol (acetaminophen), alone or in combination. Narcotics can be used with little risk of addiction, but with the caveat that they can cause cognitive changes, constipation, urine retention and respiratory depression (see section on analgesics). Codeine... 

Opioids such as diamorphine, pethidine, and pentazocine strongly inhibit gastric emptying and greatly reduce the absorption rate of paracetamol. Codeine, however, has no significant effect on paracetamol absorption. Morphine and diamorphine have been shown to reduce the absorption of antiarrhyth-mics such as mexiletine in patients with myocardial infarction. 

Stated content/tablet = aspirin 250 mg, paracetamol 250 mg, codeine phosphate... 

Weight of tablet powder taken for analysis = 0.1228 g Weight of t-butanol internal standard added = 8.0 mg Area of internal standard peak = 7.2 Area of aspirin CH3 peak = 5.65 Area of paracetamol CH3 peak = 6.73 Codeine phosphate CH3 peak = 0.115 MW t-butanol = 74.1 MW aspirin = 180.2 MW paracetamol = 151.2 MW codeine phosphate = 397.4 Number of protons in t-butyl group = 9... 

Number of protons in methyl groups of aspirin, paracetamol and codeine = 3. Calculation of the paracetamol in the tablets is shown in Example 8.2. 

From the above data calculate the percentage of stated content for paracetamol and codeine phosphate. 

Something of a stereotype now follows, but in a good cause to illustrate some practical points in management of minor opioid misuse. I would contend that there is a syndrome of a classic case of someone who becomes dependent on paracetamol and codeine combinations, or dihydrocodeine, dextropropoxyphene or something similar, with the following features ... 

Codeine, one of the principal alkaloids of opium, has an analgesic efficacy much lower than other opioids, due to an extremely low affinity for opioid receptors. It is approximately one-sixth as potent as morphine. It has a low abuse potential. In contrast to other opioids, with the exception of oxycodone, codeine is relatively more effective when administered orally than parenterally. This is due to methylation at the C3 site on the phenyl ring (Figure 7.3), which may protect it from conjugating enzymes. It is used in the management of mild-to-moderate pain, often in combination with non-opioid analgesics, such as aspirin or paracetamol. It is valuable as an antitussive and for the treatment of diarrhoea. Side effects are uncommon and respiratory depression, even with large doses, is seldom a problem. 

Dosages and routes of administration Codeine is used orally in single doses of 30 to 60 mg up to a total dose of 240 mg per day for pain relief. Codeine is used in the form of different salts such as hydrochloride, phosphate and sulfate. To increase the duration of action, slow-release preparations have been developed. Codeine is often combined with other analgesics e.g. acetyl salicylic acid or paracetamol. For cough inhibition lower doses are sufficient. 

A 64-year-old man with type II diabetes, hypertension, and bilateral renal artery stenosis presented with confusion and dysarthria related to profound hypoglycemia (2.2 mmol/1). He was taking naproxen 500 mg bd, ramipril 2.5 mg/day, glibenclamide 2.5 mg bd, metformin 850 mg bd, a thiazide diuretic, terazosin, ranitidine, paracetamol, and codeine. His plasma creatinine concentration, previously 185 pmol/1, was 362 pmol/1 and it fell to 210 imol/l after the withdrawal of ramipril and naproxen. 

Even if we cannot yet cure arthritis, there are things we can do to alleviate its symptoms. Simple painkillers such as paracetamol, ibupro-fen and codeine can be taken, and the combination of ibuprofen with a little codeine is particularly effective, a tablet will give relief for up to 6 hours. When such painkillers are no longer strong enough, then a... 

Codeine (alone or in combination with regular paracetamol) can be helpful when paracetamol alone is insufficient. Prescribing it separately offers greater flexibility in dosing and hence pain control. 

Mrs TY is in considerable pain from her fracture. She is prescribed paracetamol 1 g four times daily and codeine 30 mg four times daily when required. She is still complaining of pain. 

This chapter concentrates on some drug choices in acute rather than chronic pain, but the same principles can be used to determine the appropriateness of other types of analgesic. The drugs considered in this section are paracetamol, non-steroidal anti-inflammatories (NSAIDs specifically diclofenac, ibuprofen, indometacin, naproxen, sulindac and tenoxicam) and opioids (codeine, dihydrocodeine, morphine, pethidine and tramadol). Unless otherwise stated, all pharmacokinetic data originate from standard reference sources [1-5] and apply to adults only. 

The opioids (e.g. codeine, dextromethorphan), NSAIDs, aspirin and paracetamol found in many over-the-counter drugs have the potential for adverse drug interactions. For more details, see Over-the-Counter Drugs. 

A 43-year-old man was admitted to hospital suffering halluoinations. He had fallen off his bike, fraotured a bone in his shoulder, and was presoribed one to two tablets of Tylenol (paracetamol plus codeine) every four to six hours for two days. He oontinued to suffer occasional hallucinations and vomiting and from jaundice. Once in hospital liver function tests on his blood indioated that he had liver damage. He died in a hepatic coma thirty hours after being admitted to hospital. It was later revealed by relatives that the patient had also treated himself with nine Tylenol tablets plus ten tablets of another preparation after the bicycle accident. Another important factor was that he regularly drank half a case (twelve bottles) of beer each day. ... 

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