Clonazepam

 Risk Factor: DM
 Class: CENTRAL NERVOUS SYSTEM DRUGS / Anticonvulsants

Contents of this page:

Fetal Risk Summary
Breast Feeding Summary
References
Questions and Answers

Fetal Risk Summary

Clonazepam is a benzodiazepine anticonvulsant that is chemically and structurally similar to diazepam (1). The drug is used either alone or in combination with other anticonvulsants.

Reproduction studies in mice and rats during organogensis at doses up to 4 and 20 times, respectively, the maximum recommended human dose of 20 mg/day for seizures [MRHD-S], and 20 and 100 times, respectively, the maximum recommended human dose of 4 mg/day for panic disorders [MRHD-P], on a mg/m2 basis, revealed no evidence of embryo or fetal effects (2). In rabbits administered doses that were 0.2 to 10 times the MRHD-S and 1 to 50 times the MRHD-P, a low, non-dose-related incidence of a similar pattern of malformations (cleft palate, open eyelid, fused sternebrae, and limb defects) was observed in all dosage groups (2). At the highest dose (twice the dose that produced reductions in maternal weight gain), intrauterine growth retardation was also observed.

In a small series of patients (N = 150) matched with nonepileptic controls, anticonvulsant therapy, including five women using clonazepam, had no effect on the incidence of pregnancy-induced hypertension, albuminuria, premature contractions, premature labor, bleeding in pregnancy, duration of labor, blood loss at delivery, cesarean sections, and vacuum extractions (3).

In a surveillance study of Michigan Medicaid recipients involving 229,101 completed pregnancies conducted between 1985 and 1992, 19 newborns had been exposed to clonazepam during the 1st trimester (F. Rosa, personal communication, FDA, 1993). Three (15.8%) major birth defects were observed (one expected), two of which were cardiovascular defects (0.2 expected). No anomalies were observed in five other categories of defects (oral clefts, spina bifida, polydactyly, limb reduction defects, and hypospadias) for which specific data were available.

A prospective study published in 1999 described the outcomes of 517 pregnancies of epileptic mothers identified at one Italian center from 1977 (4). Excluding genetic and chromosomal defects, malformations were classified as severe structural defects, mild structural defects, and deformations. Minor anomalies were not considered. Spontaneous (N=38) and early (N=20) voluntary abortions were excluded from the analysis, as were 7 pregnancies that delivered at other hospitals. Of the remaining 452 outcomes, 427 were exposed to anticonvulsants of which 313 involved monotherapy: clonazepam (N=6), carbamazepine (N=113), phenobarbital (N=83), valproate (N=44), primidone (N=35), phenytoin (N=31), and other (N=1). There were no defects in the 25 pregnancies not exposed to anticonvulsants. Of the 42 (9.3%) outcomes with malformations, 24 (5.3%) were severe, 10 (2.2%) were mild, and 8 (1.8%) were deformities. There were no malformations with clonazepam monotherapy. The investigators concluded that the anticonvulsants were the primary risk factor for an increased incidence of congenital malformations (see also Carbamazepine, Phenobarbital, Phenytoin, Primidone, and Valproic Acid) (4).

Toxicity in the newborn, apparently related to clonazepam, has been reported. Apnea, cyanosis, lethargy, and hypotonia developed at 6 hours of age in an infant of 36 weeks' gestational age exposed throughout pregnancy to an unspecified amount of clonazepam (5). There was no evidence of congenital defects in the 2750 g newborn. Cord and maternal serum levels of clonazepam were 19 and 32 ng/mL, respectively, a ratio of 0.59. Both levels were within the therapeutic range (570 ng/mL). At 18 hours of age, the clonazepam level in the infant's serum measured 4.4 ng/mL. Five episodes of prolonged apnea (1643 seconds/occurrence) were measured by pneumogram over the next 12 hours. Hypotonia and lethargy resolved within 5 days, but overt clinical apnea persisted for 10 days. Follow-up pneumograms demonstrated apnea spells until 10 weeks of age, but the presence of the drug in breast milk may have contributed to the condition (see Breast Feeding Summary). The authors concluded that apnea due to prematurity was not a significant factor. Neurologic development was normal at 5 months (5).

Breast Feeding Summary

Clonazepam is excreted into breast milk. In a woman treated with an unspecified amount of the anticonvulsant, milk concentrations remained constant between 11 and 13 ng/mL (5). The milk:maternal serum ratio was approximately 0.33. After 7 days of nursing, the infant, described above, had a serum concentration of 2.9 ng/mL. A major portion of this probably resulted from in utero exposure because the elimination half-life of clonazepam in neonates is thought to be prolonged. No evidence of drug accumulation after breast feeding was found. Persistent apneic spells, lasting until 10 weeks of age, were observed, but it was not known whether breast feeding contributed to the condition. Based on this case, the authors recommended that infants exposed in utero or during breast feeding to clonazepam should have serum levels of the drug determined and be closely monitored for central nervous system depression or apnea (5).

References

1. Reith H, Schafer H. Antiepileptic drugs during pregnancy and the lactation period. Pharmacokinetic data. Dtsch Med Wochenschr 1979;104:81823.
2. Product information. Klonopin. Roche Laboratories, 2000.
3. Hiilesmaa VK, Bardy A, Teramo K. Obstetric outcome in women with epilepsy. Am J Obstet Gynecol 1985;152:499504.
4. Canger R, Battino D, Canevini MP, Fumarola C, Guidolin L, Vignoli A, Mamoli D, Palmieri C, Molteni F, Granata T, Hassibi P, Zamperini P, Pardi G, Avanzini G. Malformations in offspring of women with epilepsy: a prospective study. Epilepsia 1999;40:12316.
5. Fisher JB, Edgren BE, Mammel MC, Coleman JM. Neonatal apnea associated with maternal clonazepam therapy: a case report. Obstet Gynecol 1985;66(Suppl):34S5S.
   
   

Questions and Answers

Can taking clonazepam while pregnant increase SIDS in an infant?

I lost to sons to SIDS while taking this medication. I have other children that are fine but i was on no medication at that time. I was also taking prozac while pregnant when i lost my sons.

You should be asking your pharmacist or a chemist about that. You should also ask your doctor. They are the ones who can give you the best information.

Anyone have information on or use klonopin/clonazepam while pregnant?

I have been getting different opinions from friends/family/doctors and wanted to see if anyone out there has any personal experience with this medication while pregnant or know of any research on it.

Yeah they told me to stop taking it. It can cause birth defects and severe problems in the pregnancy. I stopped taking it as soon as i had a positive pregnancy test an er dr said it was okay but my ob strictly said NO

PREGNANCY: Clonazepam and other benzodiazepines have been associated with fetal damage, including congenital malformations, when taken by pregnant women in their first trimester. Clonazepam is best avoided in the first trimester and probably throughout pregnancy.

http://www.medicinenet.com/clonazepam/ar...

Has anyone taken clonazepam while pregnant?

If so how the the baby? and what was the outcome?

I don't think it is very safe to take during pregnancy. I was prescribed Xanax before i became pregnant and i stopped taking that immediately. Xanax and Klonopin (clonazepam) are both benzodiazapenes prescribed for anxiey and other disorders. They are both rated category C, which shows some risk to the fetus
check out the website safefetus.com for more details.

I've been taking clonazepam 1mg for 7 years I'm thinking of getting pregnant when should I stop? Female

I've been taking clonazepam 1mg and ambien CR 12.7 for 7 years and thinking of getting pregnant. I know Clonazepam has shown to casue severe birth defects. How long do these meds take to completely come out of my system so I have a safe pregnancy and prevent birth defects. When should I stop taking it befor getting pregnant? I'm a 30 years old female

I have been taking 1 mg/day of clonazepam for about as long as you. I cannot comment on the pregnancy issue, but I do know that there are unbearable withdrawal symptoms with this medication, so you need to work out a dosage schedule with your doctor.

I just found out I am pregnant and have been weaing off clonazepam.?

I was wondering if anyone has had a successful pregnancy. I know it is a class C and there are risks. I am on a pretty high does 1.25mg at the moment. I need to work so I cannot rush coming off this stuff. Can anyone share with me positive success stories. Or people who have come off a similar amount quickly? Thanks

I was on Lorazepam 1.50 mg daily when I found out I was prego at 5 weeks. I couldn't just quit either b/c of risks of seizures. I was also on Darvocets for the first two weeks gestation b/c my doctor thought I had an ovarian cyst that was causing my cramps b/c I have a history of them. Lorazepam is a class D & the Darvocet is a class C. I was able to stop taking the Lorazepam daily, but b/c of a severe generalized anxiety disorder & I mean...SEVERE, sometimes I shake & can't talk to people or even take a shower! I also have a very busy two year old. I had to occasionaly take an 0.5 mg throughout my entire pregancy. Maybe once a week in all trimesters. Only on the days I couldn't function. I am now 37 weeks along & my doctors say that baby appears healthy & my sonograms have shown that as well. I am being induced on FEb. 26th & would be more than happy to email u & let you know if any negative effects were present at birth. But, like all benzos, the risks are in first trimester w/ rare chances of birth defects & when taken daily in the last few weeks of pregnancy there are reports of withdrawals, poor feeding & lower apgar scores. The studies which concluded birth defects were tests given to rats & rabbits. At 400 times the normal human dose. So, I wouldn't worry about it. I worried terribly but my doctor told me if anything bad happened inutero, I would have miscarried. Your sonogram will help you feel better.

Pregnant and I am taking Clonazepam?

I have GAD and I am on Clonazepam. Has any other woman out there been on it during pregnancy and had a healthy baby?

Clonazepam is definately a mutagenic and my doctor took me off it the moment I found out I was pregnant. It didn't matter - my baby still had a birth defect and died, and my doctor said it had happened so early that I probably hadn't even realied I was pregnant yet (like in the first week or two).
There is no proof that the drug did it, but the baby I am carrying now is fine, and I stopped taking it a month before I got pregnant this time.
I'm not telling you this to scare you, but just to encourage you to get every possible prenantal testing as early as you possibly can so if there's a problem it can be detected asap.
I never even took high doses - 1 mg as needed for a panic attack, usually meaning one or two pills a week.

My wife found out that she is pregnant. 4-5 weeks. what are the possible side affects of topamax& clonazepam?

Both of these medications were of course prescribed. She was also being weaned off of the clonazepam. Needless to say, as was the case with our first daughter, no toxins of any kind will be entering her body. At 4-5 weeks, is there still a risk of side affects on the fetus?

Go talk to a REAL doctor and get their advice-- people here are not qualified to tell you for sure.......that is an important question for your baby....and wouldn't you want as close as a "right" answer as possible?? then, go talk to an Obstetrics doctor.

Pregnant medication Rivotril (Clonazepam)?

I am currently 9 weeks into 1st pregancy and as it was a lovely but total suprise for the first month I was taking normal medication for spinal problems but suspended all but rivotril as soon as I found out.I have been on rivotril for a year for pain and insomnia and although I have reduced the dose from 10 to 5 drops daily any less and I do not sleep a wink.I am worried about the ill effects on the baby but my doctors have various theories:is there anything natural I can take to help me sleep? Thanks for your time.Previously I was on Lyrica, Alanerv and NSAIDS.

Clonazepam crosses the placenta. Benzodiazepine(the type of medication clonazepam,alprazolam,etc are) use during pregnancy is associated with increased risk of congenital malformations. Nonteratogenic effects (including neonatal flaccidity, respiratory and feeding problems, and withdrawal symptoms) during the postnatal period have also been reported with benzodiazepine use.

Did you check with your doctor or pharmacist? You really need to discuss this with them as soon as possible to properly weigh the risks against the benefits. You NEVER take any medications during pregnancy without first consulting with your doctor.

Is a pot belly a side effect of lexapro? Or Clonazepam - generic of klonopin?

I started taking lexapro and clonazepam about 2 months ago. I have also been trying to lose weight for the past few months. So far I do keep losing weight (25 pounds so far) but my belly is getting bigger! I am not pregnant or anything. I am losing weight everywhere except my belly, which is getting bigger. Anyone else ever experience this on both or one of these drugs?

Probably the Clonazepam. I took Lexapro and it had no effect on my weight.

Those pills are awesome.