Showing posts with label side effects. Show all posts
Showing posts with label side effects. Show all posts

Wednesday, July 20, 2016

IMPORTANT INFORMATION ABOUT LEVODOPA USE IN PARKINSON’S DISEASE

IMPORTANT INFORMATION ABOUT LEVODOPA USE IN PARKINSON’S DISEASE


Levodopa is one of the most important medicines used for treating Parkinson’s disease (PD). It is sold in combination of levodopa and carbidopa. The commonly used brand names for this medicine are syndopa, sinemet, tidomet and duodopa. Levodopa is very useful in ameliorating the symptoms of PD, especially the tremors and rigidity. However, there are several important points of note regarding its use. The current article highlights a few of them.

1. Try to avoid levodopa use in early PD: Though levodopa is very effective in controlling symptoms of PD even in early stage, it is better to avoid using it in early PD. This is because the risk of dyskinesia (abnormal movements as a side effect of levodopa) and rapid wearing off (reduced efficacy of levodopa) are more common, if levodopa is started early in the course of disease. Also, levodopa loses the efficacy after longer use, so, it makes sense to start it later.

2. Use the lowest effective dose of levodopa: It may be tempting to use levodopa at a higher dose or more frequently, as the symptom control would be better with that. However, for the same reason mentioned above, it is better to use levodopa at the lowest possible dose, and as less frequently as possible.

3. Take levodopa on empty stomach: Presence of food in stomach may interfere with the absorption of levodopa; so, it is better to take levodopa on empty stomach. In the initial days of starting levodopa, there may be nausea or vomiting, so, it may be taken after food or snacks.

4. Reduce or evenly space the amount of protein intake: High protein diet prevents proper absorption of levodopa. So, the protein intake should be evenly spaced out in the day; or better, it can be shifted to dinner time (as most doses of levodopa are taken before dinner time).

5. Avoid pyridoxine (vitamin B6) intake: Pyridoxine can reduce the effects of levodopa, if taken alone. However, pyridoxine does not interfere with the effects, if levodopa is taken along with carbidopa (as in most cases).

6. Hallucinations and psychosis can be a side effect of levodopa: Use of levodopa does increase the risk of visual and auditory hallucinations, and other psychotic reactions (agitation, anger, irritability, etc). However, it is not a simple relationship. The severity & duration of PD, presence of cognitive impairment and daytime somnolence, all increase the risk of psychotic reactions with levodopa use.

7. Avoid using levodopa in late evenings: The risk of hallucinations and other psychotic reactions are higher if levodopa is used in late evenings or nights. So, avoid it at those times, as much as possible.

8. Avoid breaking, crushing or chewing the controlled release (CR) tablets: Those taking medicines such as syndopa CR, tidomet CR, etc should swallow the entire tablet, without breaking or crushing (which would reduce its efficacy).

9. There is a risk of dependence and abuse with levodopa: Levodopa increases the dopamine levels in brain and may cause effects such as euphoria (feeling of extreme happiness) and other positive mental effects. Therefore, a small group of patients with PD may increase the dose of levodopa by self and take upto 1500-2000 mg per day. These patients accept the side effects of high dose levodopa (such as hallucinations, nausea, loss of appetite), in order to experience the positive mental effects. This behavior (of dependence and abuse of levodopa) should be recognised and treated.

10. Other side effects of levodopa to watch for:
a.     Dizziness or fainting sensation on standing up (may occur due to fall in BP on standing),
b.     Feeling of nausea, vomiting, loss of appetite
c.      Sudden sleep episodes: Patients taking levodopa may fall asleep without any drowsiness or warning. It can occur while driving or doing other activities needing full concentration, which can be potentially harmful.
d.     Sleep disturbance or insomnia at nights. 

DR SUDHIR KUMAR MD (Medicine) DM (Neurology)
Senior Consultant Neurologist
Apollo Hospitals, Hyderabad, India
Phone: 0091-40-23607777/60601066
Email: drsudhirkumar@yahoo.com
Online consultation: https://www.doctorspring.com/doctors/sudhir-kumar

Sunday, August 17, 2014

Common Adverse Effects of Anti-epileptic Drugs

Common Adverse Effects of Anti-epileptic Drugs

Introduction

Epilepsy is a common condition and it is routinely treated with anti-epileptic drugs (AEDs). It is important to continue AEDs for a long time, even life long in many cases, in order to remain seizure-free. Seizure freedom depends on taking appropriate anti-epileptic drug, at a correct dose and interval, everyday for a long period of time.

When one takes drugs for long time, we need to be aware of the possible side effects. The currently used anti-epileptic drugs have been well studied in clinical trials and data about their safety and possible side effects are well known.

My aim, in this article, is to briefly summarize the common side effects of commonly used AEDs. Early recognition of side effects is important to minimise any harm due to AEDs. 

Side Effects of Phenytoin (Dilantin, Eptoin, etc)

Phenytoin is one of the commonest AED used and also among the oldest drugs. It is used in all age groups.
The main advantage is its availability in injection form; so, it is also used in emergency situations.
The other advantage is that the full dose can be started on day 1 and there is no need to start at low dose and gradually increase the dose (as we need to do with carbamazepine, oxcarbazepine, lamotrigine, etc).

Side effects of phenytoin injection- if injection is rapidly given, it can lead to low blood pressure and cardiac arrest. Also, severe drowsiness can occur.
With the use of phenytoin tablets, the following side effects should be watched for:
  • Imbalance while walking,
  • blurred vision,
  • increased facial hair,
  • coarse facies,
  • thickening of gum,
  • skin rashes. 






Gum hyperplasia due to phenytoin use






Side effects of Carbamazepine (Tegretol, tegrital, mazetol, zeptol, Zen, etc)

Carbamazepine is useful in partial or focal epilepsies and can be used in all age groups. Syrups are available for use in children. However, injection forms are not available, which prevents its use in emergency situations.

Common side effects include:

  • Dizziness,
  • Drowsiness,
  • Imbalance while walking,
  • Skin rash,
  • Lowering of sodium level (hyponatremia)

The first three side effects can be minimised if carbamazepine is started at a low dose and the dose is gradually increased over a period of days. 

Oxcarbazepine have similar side effects, however, the incidence is lesser than that of carbamazepine. 

Side Effects of Sodium valproate (Depakine, Valparin, Encorate, Valprol, etc)

Sodium valproate is effective in controlling generalised epilepsies, juvenile myoclonic epilepsy (JME), absence seizures, etc. 

Common side effects of valproate include:
  • Weight gain,
  • Tremors of hands,
  • Hair loss,
  • Liver toxicity,
  • Menstrual irregularities,
  • Increased incidence of polycystic ovary disease,
  • Pregnancy-related complications.
Sodium valproate should be avoided in patients with liver disease.

Also, it should not be used in women who are pregnant or are planning pregnancy. 

Side Effects of Levetiracetam (Keppra, levipil, levera, etc)

Levetiracetam is a newer AED and is effective in controlling various types of seizures. It is safer than most of the older AEDs. It has injection form, so, it can be used in emergency situations. Also, it is safe in all age groups and can be used in pregnant women too. 

Side effects to be watched for while using levetiracetam are:

  • General weakness,
  • Sleepiness,
  • Aggression and behavioural changes,
  • Occasional skin rashes. 
Side Effects of Lamotrigine (Lamictal, lamitor, lametec, etc)

Lamotrigine is also very effective AED, and can be safely used in children as well as pregnant women. 

Side effect to be watched for with lamotrigine use are: 


  • Nausea, vomiting, 
  • dizziness,
  • sleepiness,
  • imbalance while walking,
  • skin rash

The dose of lamotrigine should be very gradually increased to avoid skin rash.

I hope you find this article useful. Feel free to contact me at the details below. 

Dr Sudhir Kumar MD (Medicine), DM (Neurology)
Senior Consultant Neurologist
Apollo Hospitals, Hyderabad, India.

Email: drsudhirkumar@yahoo.com
Phone: 0091-40-23607777 (to fix appointment for consultation)
online consultation: http://bit.ly/Dr-Sudhir-kumar