Pain 101 Andrew Gutwein, MD, FACP

Overview Today we will cover: 1. Pain Med Myths 2. Basics 3. Conversions 4. Starting Meds and Titrating 5. Miscellaneous We will not cover: 1. PCA Pump 2. Injections and Spinal Meds 3. Specific Diseases (ex: Fibromyalgia)

Pain Med Myths 1. SOO: Demerol vs. Morphine 2. Respiratory Arrest 3. Addiction 4. Physician Oversight & Regulations

We are not rabbits damnit! Sphincter Of Oddi We are not rabbits damnit!

Respiratory Arrest You must first: relive pain before you will cause sedation before you will cause respiratory depression before you will kill someone.

Addiction Tolerance: the need to increase a drug to achieve the same effect. In clinical practice, significant opioid tolerance is uncommon. Tolerance may be present in the pain patient or the addict; by itself it is not diagnostic of addiction. Physical Dependence: development of a withdrawal reaction syndrome when a drug is suddenly discontinued or an antagonist is administered. Many patients on chronic opioids become physically dependent; its presence cannot be used to differentiate the pain patient from the addict. Psychological Dependence (Addiction): overwhelming involvement with the acquisition and use of a drug, characterized by: loss of control and use despite harm. Data suggests that opioids used to treat pain rarely lead to psychological dependence.

Addiction Vs. Pseudo-Addiction

Addiction Assessment Loss of control of drug use (has no partially filled med bottles; will not bring in bottles for verification) Adverse life consequences -Use despite harm (legal, work, social, family) Indications of drug seeking behavior (reports lost/stolen meds, requests for high-street value meds) Drug taking reliability (frequently takes extra doses, does not use meds as prescribed) Abuse of other drugs (current/past abuse of prescription or street drugs) Contact with drug culture (family or friends with substance abuse disorder) Cooperation with treatment plan (does not follow-up with referrals, or use of non-drug treatments)

Physician Oversight & Regulation Recent lawsuit for under-treatment of pain. The climate has changed! Government agencies are now more interested in making sure pain is treated, but properly and safely. Include in your records the pain Hx, how function is affected, response to Rx, and improvement in function. Use a pain contract and write on the prescription “X opioid.… for pain.” Methadone can be prescribed by office physicians for pain not just in accredited methadone maintenance programs.

The Mild Narcs Codeine - Mainly used in combination with tylenol as Tylenol #3 (30mg) or 4 (60mg). Used as 1-2 tabs PO q4 PRN. 10% of people lack the enzyme needed to make it active. Propoxyphene – 32, 65mg (1/2-1/3 as strong as codeine). Available also with tylenol as darvocet (various doses). Used as 1-2 tabs PO q4-6 PRN (depending on preparation). Tramadol – Ultram 50mg (max: 2 tabs PO 4xd). Ultram ER 100, 200, 300mg. maximum dose of 400mg/d. Also available in combination with tylenol as ultracet. About as strong as Tylenol #3. Expensive! Hydrocodone - stronger than codeine and only used in combination with tylenol as vicodin/ lortab or with ibuprofen as vicoprofen. Many different preparations - dose so that tylenol component is not toxic.

The Heavy Narcs Morphine – {careful in severe renal insufficiency}MSIR 15, 30mg (immediate release for 4 hours), MS ER 15, 30, 60, 100mg (MSContin - long acting for 8-12 hours), Kadian 10, 20, 30, 50, 60, 80, 100, 200mg (twice a day preparation), Avinza 30, 60, 90, 120mg (new once a day preparation with a maximum dose of 1600mg/d [renal toxicity], can be opened and spread on food) Hydromorphone - Dilaudid 1, 2, 4, 8mg only comes as short acting q4h (except in Canada). Oxycodone - available alone in 5/15/30mg tabs or in combination with tylenol as percocet (and other names from other companies) or with ASA as percodan. Available as Oxycodone ER (Oxycontin) 10, 15, 20, 30, 40, 60, 80mg q8-12h

The Heavy Narcs Fentanyl - comes as 12.5, 25, 50, 75, or 100 transdermal patch q48-72 hours. Also comes as Actiq transmucosal lozenge for breakthrough pain 200, 400, 600, 800, 1200, 1600mcg 4xd PRN. Also available as Fentora an acute release buccal mucosa droplet – 100, 200, 400, 600, 800mcg Methadone – comes as 5, 10, 40mg tablets. can be used q6-8 hours for chronic pain. Write on the script “for pain” otherwise beware the DEA. May need dose reduction after 2-5 days of use. Watch for QT prolongation and Torsades. No metabolites – good for CKD. Oxymorphone – now available again! (as Opana 5,10mg and Opana ER 5,10,20,40mg)

Basics Pain scale of 0-10, “0 is no pain and 10 is the pain you feel when you’ve been hit by a truck and you are about to die” Chronic pain does not wear the same face as acute pain. The patient may not look like they are in pain. Accept the patients’ subjective report of pain - do not start from the position of disbelief Acetaminophen: 650mg q4o for fever vs.1000mg 4xd (or 1350mg TID) for pain. Remember to be careful with patients that take alcohol or isoniazid, zidovudine or barbiturates. NSAID’s are all equally efficacious at equivalent doses. High doses, elderly patients, prolonged use, previous PUD, excessive alcohol intake make GIB more likely.

Basics Ketorolac is the only injectable NSAID for up to 5 days. It is comparable to moderate dose morphine. Add Tylenol or NSAID’s or both to augment narcotics. All narcotics are now written on the same kind of script as other drugs. You can give out more than one months worth for schedule 3 narcotics and you can give out 3 months worth of schedule 2 narcotics if there is a proper chronic indication written on the script. Demerol is the most emetogenic of the narcotics and its’ breakdown products can increase the risk of seizure. Do not use in chronic pain patients! (Also it really only relieves pain for 1-2 hours so don’t bother using it for the acute pain patients either.)

Basics Morphine, oxycodone (short acting) are q3o if SQ, IV or IM and q4o if PO. When converting between pain meds start the new med at 1/2 to 2/3 of the total dose of the original med because of incomplete cross tolerance. There is no ceiling dose of narcotic. Use however much you need to relieve pain. Be careful of combined pills that have acetaminophen as that ingredient will define the ceiling dosage. Always start patients on anti-constipation meds at the same time you start narcotics! Do not fall behind. Colace is not enough use senna or bisacodyl daily to BID too. Add sorbitol or lactulose for refractory cases. You need to use a stimulant; something like magnesia/magnesium hydroxide (Milk of Magnesia) or sennosides/docusate (Senokot) is a better agent. I always treat my patients proactively; they get a bowel regimen with my prescription for the opioid

Conversions Drug PO/PR SQ/IM/IV morphine 30 10 oxycodone 20 15 oxymorphone 10 hydrocodone 30 NA hydromorphone 7.5 1.5 codeine 200 130 meperidine 300 75 methadone 20(A)3-5(C) 10 heroin* 60 5 fentanyl NA 0.1 1 percocet = 2.5mg of morphine SQ *not recommended for patient use Methadone is not an easy drug to use in many patients. Although it is inexpensive, it has a long half-life, and it tends to accumulate, even though its effective half-life for pain -- its analgesic half-life -- tends to be short. Patients need treatment intervals of every 8 hours, every 6 hours when they are used to methadone. If you are not careful, the drug tends to accumulate, and patients may have increased adverse effects over time. Conversion tables are often inaccurate in patients on methadone because the treatment trials have been done for acute pain. When patients are opioid-tolerant, they have been on the medication a long time. The treatment scales -- the conversion tables -- are much lower for methadone. So patients may talk about using 3 mg of morphine compared with 1 mg of methadone in acute pain setting; whereas, it could be as low as 10 to 1 -- 10 mg of morphine compared with 1 mg of methadone -- in a chronic opioid-tolerant patient. Methadone also prolongs QRS interval, especially at high doses, and it can be cardiotoxic. There have been reported deaths of patients on methadone that have been related to the cardiotoxic effects, and this toxicity has not been identified, especially in the primary care community.

Conversions fentanyl mcg/hr morphine mg/24hr PO 25 45-134 50 135-224 25 45-134 50 135-224 75 225-314 100 315-404 125 405-494 150 495-584 175 585-674 200 675-764 225 765-854 250 855-944 275 945-1034 300 1035-1124

Starting Meds and Titrating Start morphine 5-10mg SQ q3o (or 15-30mg PO) in narcotic naive healthy pt. Double this baseline dosage if no effect in 30-60 min. Also order breakthrough pain meds. Use about 1/4 of the baseline dosage. If using morphine 30mg PO q4o, then the breakthrough order is morphine elixir (pills only come in 15/30) 8mg PO q1o. To switch to Morphine ER total the 24 hour morphine dose and give 1/2 q12o (or 1/3 q8o for those in whom the effect wears off after 8 hours). Remember to add Tylenol for added effect. If changing to Fentanyl patch, remember it has a delayed onset of 12 hours and 14-24 hours of residual action once removed.

Starting Meds and Titrating On the outpatient side, when a patient is on a long acting preparation (usually of morphine, oxycodone or fentanyl) remember to give them something for breakthrough pain! One can use tylenol #3/4, vicodin/lortab, percocet, MSIR, actiq transmucosal for breakthrough. Use about 10% of the long acting dose. At every visit remember to find out how much breakthrough they needed so you can add that back into the long acting preparation so they are less likely to need breakthrough next time.

Miscellaneous For elderly consider hydromorphone and oxycodone as they have no active metabolites and thus you do not need to worry about liver/renal function. Be careful in renal insufficiency with morphine, tramadol and propoxyphene as they can accumulate toxic metabolites and cause agitation and confusion. For persons on Xmg of MScontin q12o who come in unable to take PO, you can use 1/3(2X) IV over 24o. Radiation therapy, injectable radionuclides and bisphosphonates can be used to help bone pain (mets). TCA’s, Duloxetine, Venlafaxine, corticosteroids and anti- epileptics (neurontin, pregabalin, carbamazepine, phenytoin, topiramate, depakote, lamictal) can be used for neuropathic pain in certain situations.

Miscellaneous Lidocaine patch can be used for post-herpetic neuralgia. Topical - capsaicin cream (zostrix) can be used for neuropathic pain and OA – lidocaine/prilocaine (EMLA) for cutaneous anesthesia Clonidine patch (catapres) can be used for sympathetically maintained pain. Dexamethasone 16-100mg/d in divided doses can reduce vasogenic edema in cord compression. Dextroamphetamine and methylphenidate 2.5-5.0 mg at breakfast and lunch can decrease opioid sedation. modafinil (used for narcolepsy) can do this as well. If you need to use naloxone, use it diluted in 10cc, 1 cc at a time. If you completely reverse, the person will go through withdrawal.

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