Drug drug interaction

My friend, XY is a counsellor. She has a client who was taking Valdoxan (agomelatine) and Seroquel (Quetiapine) for depression. Recently her client was stress and smoke marijuana / cannabis at the same time. XY asked whether there are any drug-drug interaction among these 3 drugs and can that cause panic attack in her client? 

Identify drug-drug interaction on a prescription is also one of the job of pharmacist. 90% of the time, drug-drug interaction was not significant and thus do not require any adjustment but just closer monitoring. However, sometime, drug-drug interaction require some of the drugs on the prescription to be changed to a safer alternative.

A check on agomelatine showed that this drug is available in Malaysia. It is a melatonin type of antidepressant from Servier company. It is often used as 25mg once daily at bedtime. As it is a CYP1A2 substrate, the drug is not suitable to be co-administered with flucoxamine and ciprofloxacin, which are potent CYP1A2 inhibitor. 

There are few drug interaction checker available online and on mobile apps. The reliable one include www.drugs.com, MIMS gateway and Micromedex drug interaction checker. Upon entering the 3 drugs in the checker found that interaction exist between quetiapine and cannabis. Using both agents together increase sedation, drowsiness and dizziness. The patient will also not able to concentrate and has trouble making judgment. Panic attack is not listed in it and may require further search on certain case reports or other literature. 

Pharmacists often overlook drug-drug interaction due to lack of knowledge and not familiar with the prescribed medications. Regular updates on drugs, using interaction checker and create pop-up messages in the computer system will help us in identifying these interaction.

当药剂师进军饮食业

静脉营养 (Parenteral Nutrition)是把一种特别配置的营养液，透过管子从血管（静脉）输送全身的营养補助法。由于营养液不是透过嘴巴进入身体，无须经过咀嚼和肠胃的消化，因此也称作肠外营养。

我们每天所吃的食物都必须经过肠胃的消化和吸收，才能转换成身体所需的能量。举个例子，米饭中的碳水化和物，肉类中的蛋白质，食物中的油脂；都必须转换成葡萄糖（glucose），氨基酸（amino acids）和脂肪酸（fatty acids）才能被身体所吸收和使用。因此，一旦肠胃功能出现问题，并在超过七天都无法进食，我们就必须通过其他途径去供应病人身体所需的能量。这些病人包括：患有肠癌的病人，因为肿瘤太大而造成肠阻塞；一些因为早产而体重过轻，并还无法用母乳喂养的婴儿；患有溃疡性结肠炎的病人；一些肠胃功能正常，但是却营养不良，并需要进行各项治疗和手术的癌症病人等等。

医院里提供静脉营养的服务，通常是由一队称为营养支持小组（nutrition support team）的医务人员所负责。小组里有医生，药剂师，护士和营养师。药剂师主要的职责包括负责营养液的调配与供应。静脉营养所使用的营养液究竟是何方神圣？其实营养液的包装，类似我们在路边摊向小贩购买的汽水；那种装入塑胶袋，用塑胶绳绑起一角，并在另一角插入吸管的包装饮料。只是，其分别在于路边摊的饮料是喝进肚子，经过消化才能转换成葡萄糖被吸收。可是营养液却是直接输入静脉，并含有能够直接被人体使用的多种营养元素：如葡萄糖，蛋白质，脂肪酸， 电解质（electrolytes）, 矿物质(minerals)，微量元素（trace elements），无需像其他食物般需要经过冗长的消化过程。

市面上有两种商业配方的三合一和二合一包装营养液供医务人员选购。但是，当病人的情况比较特殊，或当商业配方不适合，就需要人工配置处方的营养液。药剂师就是负责按照医疗团队所定下的处方，根据病人的身高体重，体内电解质，肾脏和肝脏功能等等，计算出病人所需的卡路里和其他营养，混合原料并包装。我们必须在特别的配置室里（clean room）穿上类似太空装，将原料以特定的排列混合。由于营养液是直接透入血管，所以其制作过程非常严谨，以便降低微生物，细菌和毒素的污染，并确保混合后营养液的安全和稳定性。

尽管静脉营养補助法有许多好处，能帮助病人在短期内取得所需的能量，但它从来都不是提供营养的最佳途径，家属不应要求医生为病人输入营养液。如果病人情况允许，医疗团队通常都会先通过插管直达肠胃的方法，把流质食物送入病人肠胃（管灌，tube feeding）或鼓励病人口服食物（oral feeding）。因为这种经过消化系统的方法更符合人的生理状态，而保护肠胃功能。

 

孕妇可以吃药吗？

每一个准妈妈的怀孕历程都不同。有的和平时一样， 就像美国一个距离预产期两个星期的孕妇竟然还能挺着大肚子举重。 可是有的孕妇却在怀孕期间吃尽了苦头，身体不断出状况。而在怀孕期间生病能吃药吗？

其实，并不是所有的药物都对胎儿有害。根据世界卫生组织网站2014年1月的资料显示，每33个婴儿当中，有一个会患有先天性疾病或身体缺陷。药物所导致 的先天性异常只占了少数一部分。其他因素如营养不良，遗传，传染病，化学品，高剂量辐射，烟，酒和环境等因素其实更为普遍。而这当中有一半以上都很难找出 具体的原因。

为了孕妇的安全，不同国家把药物在怀孕期间分类的方法都不同。我国根据美国食品和药物管理局 (FDA) 的标准，把药物分类成A, B, C, D, X 五个等级。A和B级的药物一般都可安全使用，C和D级的药物则可能会对胎儿造成损害，可是却对孕妇的病况有益。而X级的药品属于怀孕中禁止被使用的药物如口服暗疮药isotretinoin。

除了药物的等级，其他因素如药物的剂量，持续服用的时间和在哪一个怀孕周期服用都会对胎儿有影响。在卵子受精后20至55天，或停经后5至10周是胎儿器 官成型期 (organogenesis) 。在这时期，孕妇不应擅自服药。有的时候，同样的一种药物在怀孕早期的和晚期会带来不同的影响。 比如在怀孕早期，孕妇并不适合服用有pseudoephedrine成分的感冒药。但是在怀孕晚期如果短暂如一至两天使用却可以被接受。

孕妇也不应擅自停药。如果在怀孕前就患有慢性疾病如高血压，糖尿病，癫痫，气喘等，此类疾病如果控制不当所带来的不良影响远比服用药物还来得高。举个例子，许多常见的高血压药物如perindopril, losartan等并不适合在怀孕期使用，必须得换成另一种药物。患有高血压的准妈妈不应擅自停药，而应在计划怀孕前就咨询医生或药剂师，她们所服用的药物是否适合？

其他怀孕期常见的疾病如孕吐，感冒，胃灼热，便秘，痔疮，头疼， 妊娠期糖尿病和高血压，有许多A和B级的药物可以使用。比如发烧药paracetamol,感冒药loratadine,咳嗽药diphenhydramine,胃药ranitidine，antacids和胰岛素等等。孕妇可向医生或药剂师询问药物的等级并商量到底她们的情况是否该服药。

 

旅游六大常用药品

旅行是一个让身心充电的好方法。不管您是独自上路还是全家老少一齐出动，请记得携带一些简单的药品以备不时之需。以下是六种旅游常用药品供大家参考。

1）感冒药

感冒病毒容易在人潮多和空气不流通的地方传播。除此以外，面对大幅度气候及温度转换也会容易让人患上感冒。备有退烧药如 paracetamol,能有效退热和减轻咽喉不适。令外， antihistamines能舒缓流鼻水和打喷嚏等症状。

2）口服补液盐

如果不慎吃了不卫生的食物而导致轻微的腹泻和呕吐，及时补充口服补液盐，oral rehydration salt能帮助补充身体流失的盐分和水分。此外，一些能吸附毒素的药品如charcoal和smectites，和减少肠胃蠕动的药品如loperamide 和atropine diphenoxylate 能暂停腹泻的症状，都是不错的旅游良伴。

3）胃药

品尝美食是旅途中不可或缺的。如果吃了太多辛辣，煎炸和油腻的食物，再加上因为赶路而没有定时进食，经常会引起消化不良，造成上腹部疼痛及不适。这时候胃药如小包装方便携带的液状antacids,或者胃片能帮助减少疼痛。其他口服胃药如ranitidine, famotidine 药效持续时间较长，适合旅途使用。

4）过敏药

若旅途中接触一些新物品，如穿戴新饰品或者碰触动植物而出现皮肤红肿，可以口服antihistamines和擦上消炎药膏如hydrocortisone。

5） 晕车药

感觉晕头转向，随即伴有噁心和呕吐的症状不只发生在车里，也常见于其他交通工具如飞机，船和火车上。旅客可在乘搭交通工具半小时前服用dimenhydrynate 和meclozine 等药品以避免不适。只是此类药物能导致昏昏欲睡。

6） 外用药品（外用止痛药，驱蚊剂，防晒霜）

外用止痛药如含有ketoprofen,diclofenac 成分的药膏和贴片能减轻因常久保持同一坐姿或步行太多而引起的肩膀酸痛和肌肉疼痛。此类外用的止痛药不逊于口服止痛药，而且能够避免口服止痛药所带来的胃痛和胀气等不适。另外，若到郊外露营或者郊游要避免被蚊虫叮咬，旅客们可穿上长袖衣裤并在衣服上喷上驱蚊剂。药剂行出售的驱蚊剂琳琅满目，而且多由天然的植物制作而成。最后，防晒霜能够保护我们的皮肤免受紫外线的伤害。出门时记得在半小时前擦上，并在太阳曝晒下每两个小时内重复使用。

以上所列的药品，纯属参考。旅客们也须记得携带日常服用的其他慢性疾病药物。如果发现自身或旅伴的症状在服用药物后没有改善，并有加剧的象征，请即刻到邻近的医院就医。

 

Liver abscess

There is this Indian uncle who had admitted to my ward complaining of fever for 3 days and worsening abdominal pain for 1 week. Patient is an alcoholic. Initially he was suspected to have acute calculus cholecystitis and meliodosis. However, CT scan showed that he actually had liver abscess. (a pus filled cavity in the liver).

His blood culture and sensitivity taken on admission showed present of Enterobacter Sakazakii. As there is multiple loculi, and the size of each of the loculus was small, there is no indication for surgical drainage of the abscess. Therefore the surgeons plan to start on conservative management, which is starting antbiotics treatment. So, for how long should we give the antibiotics???

There are 3 types of liver abscess, namely pyogenic, amebic and also fungal liver abscess. In this article, lets discuss pyogenic and amebic liver abscess. Pyogenic abscess is usually present as multiple loculi on the CT scan and commonly cause by gram negative enteric organism such as Klebsiella pneumonia, Enterobacteriacae, enterococcus, anaerobics. On the other hand, amebic liver abscess is usually present as single loculus caused by parasite Entamoeba histolytica. The antibiotics required for this 2 types are different.

Patient in this case received antibiotics (IV cefoperazone 1g BD and IV metronidazole) for 5 days and later discharge with Tab cefuroxime 250mg BD and Tab metronidazole 400mg TDS for 6 weeks. The careless houseman in charge only prescribed 1 week antibiotics for him. Luckily the error was later amended after being informed by us. (this HO did not even show a slight appreciation!!!!! OMG, seriously beh tahan with her "DO I CARE" face. Can't she just say THANK YOU???)

Come back to the case, the national antibiotics guidline in Malaysia back in 2008 is not clear... The guideline only mentioned that patient should be treated until clinical improvement achieved. In pyogenic liver abscess, the choice of IV antibiotics include:
IV Ampicilin + IV Metronidazole + IV Gentamicin, x 2 weeks (Effective but resistant toward ampicilin increased and Gentamicin may cause nephrotoxicitiy)
or
IV Ampicillin/sulbactam alone x 2 weeks. (metronidazole may be added if cant rule out amebic)

Then, the alternative agents include:
IV 3rd gen cephalosporin + IV Metronidazole x 2 weeks or
IV ciprofloxacin + IV Metronidazole x 2 weeks.

For amoebic liver abscess, IV metronidzole 500mg TDS may be started for 10 days and Tab Tinidzole 2g OD for 3-5 days.

Then from Sanford guideline, pyogenic liver abscess may be treated with:
IV metronidazole + (IV ceftriazone or IV ciprofloxacin or IV Pip/Tazo or IV Amp/Sulbactam)
and amebic liver abscess with metronidazole, however the duration was not mentioned.

A search on the total duration of antibiotics patient should received is unclear and inconclusive. The suggested duration include IV antibiotics for 2 to 3 weeks followed by oral anitbiotics for 3 to 12 weeks. The common practice in Hospital Selayang as informed by one of the doctor is IV antibiotics for 2 weeks followed by 6 weeks oral antibiotics.

In the Malaysia ICU antibiotic guideline, pyogenic liver abscess required 6 weeks of oral antibiotics while amebic liver abscess only require 7 to 10 days of therapy followed by a luminal agent for gut colonisation. Suggested regimen for those who is hemodynamically unstable are:
IV Pip/Tazo + IV metronidazole  ---- prefered
IV Cefepime + IV metronidazole ---- prefered
IV Meropenem + IV metronidazole ---- alternative
IV Imipenem/Cilastatin + IV metronidazole ---- alternative

Then for those who is hemodynamically stable are:
IV Ceftriaxone + IV metronidazole
IV Pip/Tazo + IV metronidazole

The SD number for patient is SD330816 for future reference.

Onychomycosis (Nail infection)

My doctor asked me regarding the choice of drug in onychomycosis (nail fungal infection) today. She informed that patient's condition was severe and topical antifungal did not help and oral antifungal may be needed in this patient.

Itraconazole can be use in this kind of patient. The dose and duration for this infection is very unique and it worth to be keep in mind.

1. For onychomycosis which involve fingernail only:
200mg BD x 1 week, then off for 3 weeks, followed by 200mg BD for another week.

2. For onychomycosis which involve toenail (Trichophyton rubrum or T. mentagrophytes):
200mg BD x 12 consecutive weeks

3. For onycomycosis (toenails with or without fingernail involvement):
200mg OD x 12 weeks OR 200mg BD x 1 week, repeat 1 week course twice with 3 week off time between each course.

Myasthenia gravis

Today we had pharmacist round in the medical ward. We had reviewed 2 patients in the medical ward. The first patient is a 78 years old Malay female who was admited for myasthenia gravis (MG) and later progress to myasthenia crisis. Patient was presented with dysphagia, ptosis, diplopia and fatigue. She was also diagnosed with new onset of atrial fibrillation, with existing hypertension and hyperlipidemia.

 

Patient was treated with tab pyridostigmine 30mg TDS for MG. and later the dose was increased to 60mg TDS. At the same time she was also given IVIG infusion 20g OD for 5 days. (0.4g/kg/day). Patient responded to the treatment. However, she still has dysphagia upon review. After IVIG infusion was completed, Tab prednisolone 50mg OD (1mg/kg) was later started for MG and there is plan to initiate immunosuppressant such as Azathioprine or cyclosporine in this patient. These medications are usually required for lifelong unless the culprit organ of secreting antibody has been removed. In the ward, patient's hypertension was also treated with tab amlodipine 10mg OD and her lipid profile showed that total cholesterol was 6 and the LDL was 5.01, as a result, tab simvastatin 20mg was later increased to 40mg ON.

 

Important point of myasthenia gravis include this is an autoimmune disease. Usually affecting voluntary muscle and may cause severe fatigue and respiratory distress. The common cause influde hyperactive thymus. Thymus is an organ that we used during childhood to produce T-lymphocytes, but the organ became dormant in adulthood. However in MG, the thymus gland is hyperactive and this required removal of thymus if the condition was severe.

 

Questions raised during the round included why treatment was not initiated for atrial fibrillation. Suggestions was made to score the patient according to CHA2DS2-VASc score and assess the bleeding risk according to HAS-BLED. I score the patient myself. Total CHA2DS2-VASc score: 4, patient is a candidate for anticoagulation and should be counselled on starting warfarin.

 

C-Chronic heart failure history - 0/1

H-Hypertension history - 1/1

A-Age>75 - 2/2

D-Diabetes mellitus - 0/1

S-Stroke history - 0/2

V-Vascular disease history - 0/1

A-Age 65 to 74 - 0/1

Sex-Female - 1

 

H-Hypertension history

A-Age>65, alcohol usage history

S-Stroke history

B-Prior major bleeding history

L-Labile INR

E-Medication usage predispose to bleeding.

D-Renal / liver disease

 

HAS-BLED score was 2: hypertension and age. The risk is low. If AF is confirmed, suggestion should be made to start warfarin.

 

Questions raised also include should the simvastatin be discontinued as simvastatin may cause muscle weakness and further worsen patient's condition. I suggested that simvastatin may be continued for short period of time and to monitor her condition and only discontinued when patient showed symptoms of muscle weakness again.

 

A list of drugs which should be used cautiously in patient with MG as these medications may worsen patient's symptoms upon using was also mentioned. This include phenytoin, beta blocker, loperamide, aminoglycoside, tetracycline, sulfonamide, fluoroquinolone, colistin, Quinidine, CCB. Further list can refer to

 

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=1&ved=0CCoQFjAA&url=http%3A%2F%2Fwww.myasthenia.org%2FLinkClick.aspx%3Ffileticket%3DJuFvZPPq2vg%253D&ei=ErWxUs-NC8eHrQfolIDwDA&usg=AFQjCNF---Bkimg54LK4kCXHNP9yf40qRg&sig2=MtfZTA5OkgTD4AEn_aNGEQ

 

 

 

We then proceed to the next patient in the ward next door. 

 

 

 

AVM

LLS is a 27years old lady with arteriovenous malformation at her right hand. It is a congenital disease where the patient's artery connected directly to the vein without passing the capillaries. This abnormal connection is fragile and will bleed easily. During admission, she was bleeding profusely and her hemoglobin level dropped to a dangerous 4g/L (normal is about 10-12g/L)

This is my first time seeing a life blood spurting artery. Upon opening the bandage on the right hand, her blood spurt out like a burst pipe and the site still continue to bleed even the doctor apply direct pressure and inflated the blood pressure hand cuff to reduce blood flow to the site. I was just standing right beside the young girl staring at the blood... IT IS SO SCARY. The blood current is so strong. It is just like the garden host that started splashing without control but this time, it is blood coming out from it rather than water.

The surgeon looks so relax!!! I was pretending to be calm too. With my heart start pumping like mad and blood gushing to my face, I actually still able to talk to the patient and try to divert her attention. This is so unbelievable. Mr C just do a few stitches on the patient hand, and the wound stop bleeding. It is so amazing. The girl was then send to the operation theater for a proper procedure. Wish the girl will be fine.

Getting treatment in a government funded hospital is really depend on luck. If the patient is lucky and met some senior and experienced doctors like Mr C, I will be sure that they had done a lot of good deed in the past. The society nowadays judge the success of one person based on the car they are driving and the house they are staying. In order to support their status and their luxurious lifestyle, many doctors nowadays use their knowledge to earn money. I sincerely wish Mr C always healthy and happy. Hope he will have a long age and to safe more people.